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When it comes to hedges, there are certain things we want from the plants we use. When choosing which plant to buy, it is best to go through a check-list of what you need, and what the different choices offer. Let’s look at the most important features and see how some common hedging plants stand up to some scrutiny. If you use check off these features against the different plants you are considering, you can eliminate the guess-work and be able to make the right choice for what is often an investment that will last for 30 years or more.

Should be evergreen

It is true that the nearest thing to an ‘instant hedge’ will be a deciduous plant, perhaps one of the fast-growing willows. These can grow 6 feet or more in a season, which is much faster than any evergreen. But the downside is pretty much a deal-breaker. For several months of the year you can see straight through your hedge, destroying any ideas of privacy. Now sometimes this doesn’t matter. For example, in a larger garden it is common to use internal dividing hedges, and in winter these can be bare without it becoming an issue. In fact, letting the low winter sun through can be a big plus factor. Trees like beech make beautiful deciduous hedges, and beech has the advantage of often holding its brown leaves for most of the winter anyway.

But when privacy is an issue – and for most gardeners it is the main reason for planting hedges – the evergreen plants are really the only way to go.

Should stay green all year round

A problem with some evergreens is discoloration during winter. The foliage of some plants turns brown – usually called ‘bronzy’ – or scorches with the combination of sun and low temperatures. Since in winter your hedges are often the most prominent thing in your garden, how much nicer is it if they are rich green through the coldest months? It might take some research to confirm that the plant you are looking at does this – nobody advertises defects – but two good choices that are always green are Thuja Green Giant and Emerald Green Arborvitae.

Should grow fast

Every plant takes time to grow to where we want it, but some of course take longer than others. Only you know how quickly you want a mature hedge, or how long you are prepared to wait. Some trees that produce very long-lived and beautiful hedges take a long time to get there – yew trees for example. Others do it very fast – Thuja Green Giant will add at least 3 feet a year from the second year of planting until about the fifth, after which it will slow down to a foot or two. But that is ten feet in 3 years, and often enough to give you what you need. That tree has been proven in research to be the fastest-growing evergreen, but climate plays a part too, and in colder areas you cannot expect suitable plants to grow as well. Emerald Green Arborvitae is great in cold zones – it is hardy to at least zone 3 – but it will only grow a foot or so in a year.

Should be hardy

Make sure the plant you choose is well-matched for your growing zone. If you don’t already know it, it is easy to enter your postcode and find out. Often it is possible to ‘push’ your hardiness zone with many plants, and grow one zone colder than it says, but don’t try this for hedges, because they are too important to risk them being wiped out in a harsh winter. So always select plants that are thoroughly hardy in your zone. This applies at both ends – something often overlooked when you live in warmer places.

For example, if you live in a moderate zone – usually considered to be zones 5 to 7 – then Thuja Green Giant is the perfect choice. In colder zones use Emerald Green Arborvitae, as it is hardy throughout zone 3. It also makes a good choice for a smaller hedge in warmer zones up to 7. In warmer areas Thuja Green Giant will do well in zones 8 and 9 if your local climate is not too dry. If you have long, hot, very dry summers (often called a ‘Mediterranean climate’) then a plant that thrives around the Mediterranean is the best choice – Italian Cypress, either in its natural deep green or in one of the bluer forms, is very drought resistant indeed, and grows very well in hot and dry locations, as well as making great specimens in areas as cool as zone 7.

Should tolerate both sun and shade

It is a bit unusual to be putting in a long hedge that is always in full sun for its entire length. Except for yew trees, which tolerate shade well, but grow slowly, most evergreens do best in sun. But if your hedge will pass through both sun and shade you want to choose a plant with reasonable shade tolerance. Most Arborvitae need plenty of sun, or they grow very slowly into thin, open plants. But Thuja Green Giant will grow almost as well in 50% shade as it does in full sun, making it a great choice for this difficult but common situation.

Should be drought resistant

We accept that for the first few years we are going to give our new hedges some care, in the form of regular watering in summer. Once they become established, though, we would like to be able to leave them to take care of themselves. If we only have to trim once or twice a year, that would be ideal, as most people have limited time for their gardens. Summers can vary a lot, and even in places which normally have regular summer rain, drought year happen. So look for good drought resistance in established plants, unless you have unlimited water available, and a full irrigation system. Thuja Green Giant is more drought resistant than most evergreens, although Italian Cypress certainly beats it, surviving months of dryness without damage.

Ready to choose?

Now you have a better idea of what to look for, making that final choice of plant variety for your new hedge is a lot easier, and you are much more likely to have a top-rate outcome, and soon see the hedge of your dreams, right in your own garden.

Now that we have entered the summer months, the spring planting season has drawn to a close. That doesn’t mean that we need to stop planting. One of the great benefits of plants growing in pots is that they can be planted at any time of year.

This is very different from 30 or 40 years ago, when a lot of plants – evergreens in particular – were grown in fields and dug out of the ground in spring or early fall, and then sold for immediate planting. This change doesn’t mean, though, that we can treat summer plantings the same way as we might a spring or fall planting. While bargains are often available in summer, as nurseries clear their remaining spring stock, they can need some additional care, if they are to succeed, and not suffer any set-backs. Let’s look at the way to handle summer planting of evergreen bushes, such as Thuja Green Giant, Emerald Green Arborvitae, or any of the multitude of ornamental evergreens available to us.

Care of Evergreens Before Planting

Once your evergreens arrive home, either from a shipping delivery, or from a shopping expedition to a garden center, you need care. In spring or fall we can often just put them in the garden for a few days, and more-or-less leave them to their own devices. Not in summer.

Shade is best

Find a shady spot in your garden, and unwrap the plants immediately, including any string that has been used to hold them together during shipping. If you have bought several, perhaps for a hedge or screen, then space them out a little, so that the air can circulate around them. Close packing can lead to yellowing, or fungal diseases.

Water regularly

Water the pots thoroughly, so that water drains out through the holes in the bottom of the pot. Do not stand them in saucers – let the water run away into the ground. If you are not planting for a few days, check the root balls each day, and water if the top inch is dry.

Shade the pots

Sometimes, in a new garden, you may not have a shady area available, since you have no large trees yet. There may be a zone of shade along a fence, or on the north-facing side of your house, but if not, then place them in the sun. In this situation the foliage will normally be fine in full sun, but there is a danger that the pots, which are usually black, will absorb a lot of heat from the sun’s rays. This can raise the temperature inside the pot, damaging the roots. In this situation, wrap some old burlap, or some scrap cardboard, around the pots. If you have lots of plants, arrange them in a block, and put some shading on the south and west sides, which will be the ones that pick up the most heat. Cardboard, or some burlap attached to sticks works well, and so does white plastic sheeting, which will reflect the heat away.

Planting Evergreens in Hot, Dry Weather

Now you have taken care of your plants for the time you need to start planting, we can look at the planting site, and modifications to planting when you are doing it in the summer.

Preparing the planting area

In spring or fall there is usually enough rain around to mean that the soil you are planting into is damp. Often in summer it won’t be, but instead the area will be dry. For good establishment of your plants it is best if the ground is damp, so a day or two before planting, arrange for a thorough watering of the whole area, not just the planting holes. If you plant into dry soil there will be no encouragement for the roots of your plants to spread out, even more if you keep the root ball watered, so the surrounding soil needs to be damp too.

The best way to do this is to put a sprinkler on the whole area for a few hours. If you stand with a hose you may simply wet the top couple of inches, without their being time for the water to penetrate. By doing it a day or two before planting you leave time for the water to drain down, and you won’t be planting in mud. Especially if you have clay soil, allow two days for it to drain well.

(I am assuming here that you have already dug or rototilled the area and added organic material to the soil, as we have described in lots of previous blogs)

Prepare the plants

The night before you plant, give all the pots a good soak. That was easy!

Planting time is here

Finally, we get to do the planting. Since you have already prepared the area, just remove enough soil to fit the pot. If you are planting into soil that has not been prepared, take out a hole three times the diameter of the pot, and mix some organic material into the soil you removed from the hole. Just dig the hole to the depth of the container, and roughen up the bottom with a digging fork, or spade.

If you are planting several bushes, don’t remove them all from the pots before starting. The delicate roots will dry and burn quickly in the hot sun, or dry wind, and die. Only remove the pot when you are ready to immediately put the plant into the hole.

Put back two-thirds of the soil, and firm it down around the root-ball. Now fill the hole with water, and let it drain away completely. Replace the rest of the soil and firm it down gently.

After you finish planting, water the whole area well, and add a layer of mulch – organic material like compost or manure, or shredded bark, are better materials than gravel and bark chips, as they will feed the soil as they break down, while reducing water loss from the soil surface. Cover an area triple the pot diameter with mulch, leaving the stem and foliage uncovered.

Caring for Newly-planted Evergreens in Summer

Watering

Newly planted bushes are entirely dependent on their root balls for water, until they send out new roots, which can take a month or more. So, in summer, let a hose run gently, close to the stem, for a while, every second day for the first week. The water around the plant over a bigger area twice a week for the first month. After that, water weekly until the end of the season.

Don’t make the common mistake of skipping a watering session because there was a summer thunderstorm. That water rarely penetrates the ground at all – scratch the surface the next morning if you don’t believe it, and you will see dry soil.

Feeding

To help your plants start growing strongly, use a liquid fertilizer for evergreens every two weeks during this first season. In the following seasons you can switch to granular feeds, which are usually cheaper, certainly quicker to apply, and work well on established plants with bigger root systems that can absorb them.

That’s It

If you follow these simple steps, you will have great success with summer planting, even in the hottest conditions, and you can take advantage of the reduced prices that are often available. Don’t put it off until the fall, or next spring – get planting now.

As the full force of summer arrives, and high temperatures are already being recorded across the country, it is time to think about protecting our plants from drought. With unlimited water and time, or automatic irrigation, it is of course no problem, but many people are making the decision to reduce their garden water usage, either by choice, because of rising water costs, or because more and more cities are placing restrictions on watering your garden, either permanently, or seasonally, which usually means exactly when your plants need it most.

While Thuja Green Giant is not a true ‘xeric’ plant, it does have considerable ability to resist seasonal drought, at least, when it is well established. So the first order of business in making your screens, hedges and specimens of this fabulous evergreen drought-proof is to establish it well. After that we need to conserve the moisture already in the soil, and when we do need to water, make sure we use as little as possible, and get it where it can do the best job of keeping your plants alive. Let’s look at those things in turn.

Establishing Thuja Green Giant for Drought Resistance

Moisture levels in soil increase as we go down, until very often we reach a level where ground water is permanent, and there is abundant water available. In practice that is usually too far down for tree roots to reach, but every few inches deeper means more water, so the first step in making your plants drought-proof is to make their roots spread as deeply as possible. As well, a larger volume of soil from the surface down will make it easier for your plants to find enough water.

Deep Soil Preparation

This is the key, and it means a little extra work when preparing your planting site. Although you may be spacing your plants 5, 6, 7, or 8 feet apart, digging small individual holes is not ideal. A much better approach is to create a broad strip of prepared soil the whole length of your planting, as this exposes a much greater soil volume for your plants to penetrate. Run a string along the route of your hedge or screen, making sure it is 4 to 6 feet inside your property line, and then mark it a minimum of 3 feet wide. If you can, wider is even better. That whole strip should be deeply dug, either by hand to the full depth of a full-sized spade, or by rototiller.

If you use a rototiller, one quick run along the area is not enough (sorry!). It might look great, but that beauty is only ‘skin deep’, and almost certainly you have only tilled a few inches down – stick a spade in if you don’t believe it. Ideally you should pass along the area two or three times, as slowly as possible, and holding the machine back so that it digs deep. By the time you are finished the digging tines should be invisible, and deep in the ground.

Add Organic Material

Besides its nutrient properties, organic material (garden compost, animal manure, rotted leaves, etc.) is a great water-retainer. By adding it to your soil you increase the water-holding capacity greatly, without reducing air penetration, so the roots remain healthy. Remarkably, this is true of both sandy soils, where it seems obvious, and heavy clay soils, which we (wrongly) figure have lots of water in them. [Because they are so fine, clay soils don’t release a lot of the water in them – it remains trapped and unavailable to plants.] So spread a layer several inches thick across the planting area and till it in – it will really make a difference in every soil.

Water to Encourage Deep Rooting

Once planted, your new Thuja Green Giant plants need to spread their roots wide and deep, so they can access as much water as possible in future dry periods. This means watering the right way, to encourage that. At first, for perhaps the first month, the water needs of your new plants must be supplied from the roots in the root ball that was inside the pot – that is all it has. This means watering close to the stem of the plant is essential, and if the weather is hot this might be needed every 3 days. In ordinary spring and fall weather, do it weekly.

As well, we want to encourage those roots to move out from that small volume, and to spread into the surrounding soil you have carefully prepared. They won’t do that if the soil is dry, so you also need to water over a larger area than just where the root ball is. After that first month, avoid watering close to the stem, and focus on deep, weekly watering of a wide band of soil around each plant, or ideally, along the whole row. Get those roots moving out!

Maintaining Established Thuja Green Giant during Drought

Once your plants have spent that first season getting established, we now want to keep those roots spreading, but as we said earlier, getting water to them can be tricky, so we want to encourage independence and conserve what is already there.

Conserve Moisture

The classic way to conserve moisture in soil is with mulch. Any material, from plastic to paper, bark or gravel, that we lay over the soil will conserve moisture by reducing its loss from the surface. Yes, if you don’t mind the look, spreading out the local paper, or the Sunday New York Times, over the ground, and holding it down with a few rocks or some scattered earth, is a great short-term mulch. Even better is a 2-inch layer of that rich organic material you used to prepare the ground. That really is a better choice than bark, shredded wood, or stones, although cost is a significant consideration too. Rich material will rot down in two or three years and need replacing, but it will also fertilize your plants and maintain the water-holding capacity of your soil, so it is a much better choice.

If you don’t want to, or can’t mulch, then keeping the soil cultivated actually conserve moisture. The surface dries, but the broken up soil doesn’t draw much water from deeper down, and acts as a ‘soil mulch’ – it’s a useful tip, as well as keeping your planting looking great and weed-free.

Keep All the Water You Apply

If you have done things right, watering should be a last resort, and only needed during extended dry periods. Even if your plants look sad, if they are well-established, they will stay alive and come back when you can water again. If water restrictions are not in place, the simplest and most obvious way to water your plants is to grab the hose and start squirting, right? In fact, that is the worst way to do it. Large amounts of water evaporate before it reaches the ground – and the finer the spray the more you lose. So you pay for water your plants never even see. As well, you damage the soil surface, compacting the ground and drawing water more rapidly to the surface where it evaporates. (Mulch will of course prevent that compaction, another plus for doing it.)

Much better is to let water trickle gently into the soil from a slow-running hose. It will spread sideways too as the soil becomes wet, although not so much on very sandy soil. Even better is to weave a soaker hose (shown above) in and out through your hedge, as it will gently spread water over a large area, and this method uses a lot less water that standing there with a hosepipe!

About this time of year, in spring, a common distress call is about hedges that haven’t gone through the winter well. This is especially common if they were freshly planted in the fall before, and perhaps winter was severe, or very dry, or just not mild and pleasant. You step outside and see that your new Thuja Green Giant hedge is looking sad. Maybe there are some dead or brown twigs, the foliage looks yellow, maybe a few plants have been pushed over by heavy snow falls, and despite this being a tough and reliable plant, that is not what you are seeing! But don’t worry – this really is a tough plant, and with a bit of TLC you can soon have them back on their feet and growing strongly.

Get Your Thuja Green Giant Plants Growing Strongly

Firm them down and straighten them up – frost and snow can shift them around, and loosen the roots
Feed your trees and your soil – if you are planting in poor soil, adding soil microbes will bring it to life
Water – deep watering will get everything going – repeat each week for the first season
Put down a rich mulch – this will conserve moisture and feed both the soil and the plants
Tidy and trim – remove any dead or broken twigs, and trim back the tip to encourage bushy growth

Firm Down Around the Roots

In winter, when the ground freezes, the water in it expands. This lifts and loosens the soil. Sometimes this can be a good thing – in areas you plan to plant vegetables, for example – but for newly-planted bushes it loosens the root ball and makes it hard for them to send out new roots. New plants need to be in close contact with the surrounding soil, so that new roots can easily spread out from the root ball, exploring for food and water, and anchoring your trees.

If your plants seem wobbly and loose, or are crooked and not straight up, then take hold of the stem halfway down, straighten them, and use your foot to press the soil down around the root ball. They should be nice and firm in the ground, and they should be pointing straight up. If you now have footprints, take a cultivator or rake and level out the ground. Now they can get going, and you will have a good straight hedge too.

Feed Your Trees and Your Soil

If you have good soil, and an established garden, and you mulch regularly, then there is nothing wrong with using simple fertilizers that boost the levels of nutrients for your trees. Evergreens like Thuja Green Giant need plenty of nitrogen, so choose something blended for evergreens, which should have a big number at the beginning of the three-part formula on the package.

If you are starting a new garden, on a development site, or an area that has had a lot of construction activity, the chances are that the soil will be depleted. Not just of nutrients, but also of the necessary micro-organisms that create the complex soil cycles. These both break down nutrients and make them more available for your plants. There are several products available, but one of the best is Bio-Tone organic fertilizers. These blend natural, organic sources of nutrients, including those all-important micro-nutrients, with a range of specialized bacterial spores, which germinate in the soil and establish colonies. These release the nutrients, and also begin the natural development of the soil ecosystem.

Water

How often have you read the importance of watering? Well it’s true – plants can’t grow without water, especially when they are newly planted. I likely reason your Thuja Green Giant don’t look good in spring is if they were not deeply watered in late fall – something you should always do. So make up for it with a good, deep soak this spring. Rather than standing with a spray on your hose, set it up to run slowly beside the base of each plant, so that the water penetrates deeply.

Even better is to install a simple irrigation system. The easiest, yet one that is very effective, is a leaky pipe system. These are black pipes made of a porous material, that drip water all along their length. They are perfect along a hedge, undulating like a snake between the trunks, and covering further out too. You can even put a timer on the tap and set it to come on for a few hours once a week – maybe twice during hot, dry weather if your hedge is new.

Put Down Some Rich Mulch

Hopefully you added some rich organic material when you were planting, but even if you did – and especially if you didn’t – putting down a layer as a mulch is a great idea. Materials like garden compost, rotted cow, horse or sheep manures, mushroom compost, or even rotted leaves, are much, much better for your soil than using bark chips, shredded bark or pebbles. Those material might reduce water loss, but they do nothing for your soil. Rich materials build richer soil over time, and that is the secret to having your plants grow well.

A mulch layer should be 2 or 3 inches thick and cover well outside the area around the stem. Keep it away from the stems, and off the foliage, as it can rot the leaves and damage the bark. This layer will also reduce weeds, as the last thing you want is for your new hedge to have to compete with weeds for water and nutrients. Mulch can go down in late fall or early spring, and it should be renewed every few years, as it will decompose into the soil over time – which is a good thing.

Tidy and Trim the Plants

Once you have taken care of everything else, finish up by going over each plant with your pruners. Snip out any dead or damaged branches, and ones where the leaves have turned dry and brown right to the ends. This will not only make them look a whole lot better, but it will leave some room for new growth, and often stimulate it too. Thuja Green Giant will not re-sprout from branches with no leaves on them, so don’t leave any stumps. Then snip off the ends of the growing branches and straighten up the top by cutting back to all the same height. Regular trimming during the growing phase of a hedge is needed to build a strong internal structure, so don’t just let it grow to your desired height and then start trimming – that‘s a common mistake.

Now you have done all these things – which won’t take so long – you can look forward to seeing some strong growth on your new hedge, and a quick recovery to the beauty and vigor that this plant is capable of delivering.

If you do a little research, you will usually find that Thuja Green Giant Arborvitae is listed as an evergreen that needs full sun. Yet look around, and you will see good specimens and hedges of this plant growing pretty well in shade – so what’s going on?

To understand this a little better, we need to look more closely at the different types of shade in gardens. Understanding this will help you grow not only Thuja Green Giant, but all your other plants too. Basically, there are three or even four distinct types of shade found in gardens, and each of them has a different effect on plants growing in them. Once you understand the differences you will see why it is that you see the same plant doing well in shade in one place, and badly in another, including plants of Thuja Green Giant.

Types of Shade – One: Open Shade

The first type of shade we find is what is often called open shade. What is ‘open’ about it? Simple – just look up. Can you see the sky, free of tree branches or any other obstructions? If you can, then you are looking at open shade. Even though the direct rays of the sun don’t come through, the atmosphere scatters and spread the light, and all the wavelengths of sunlight are present, in a very similar balance to direct light. This is important, and it explains why many plants will grow well in these locations. We find this kind of shade on the north side of buildings (or south side, if you are reading this in Australia, New Zealand, South Africa or most of South America) and in the shadow zone cast be trees, most noticeably between fall and spring.

Sunlight contains all the wavelengths and colors of visible light – all the colors of the rainbow. Plants use mostly red, and some blue light, but not green light. This is why they look green – the green part of the light is reflected back to our eyes, and the other colors are absorbed for photosynthesis and growth. Open shade gives plants all the necessary colors, just less of them, so growth is possible, even if it is reduced. Indeed, many plants grow very well in open shade – hydrangeas for example. Especially in hot states, and in the south, some plants prefer to be in open shade, since the very strong sunlight can burn the leaves and inhibit growth.

So if you want to grow Thuja Green Giant in a place in open shade, it may grow well. Not as fast as in full sun, and it may not be quite as dense, but this reliable plant will survive and grow, especially if it gets a few hours of direct sunlight, as we will discuss a bit further down.

Types of Shade – Two: Overhead Shade, Deciduous Trees

If you look up in this kind of shade, you will see that it comes from tree branches overhead. These may be solid and dense, or they may be more open and showing some blue sky. They may be close overhead, or high up above you. The denser and closer they are, the less light there will be. This kind of shade has another disadvantage. Most of the light that reaches the ground has passed through the leaves, and the valuable red and blue colors have been extracted by the chlorophyll. This creates that lovely cool look in shady spots – at least to us – but for plants growing in these areas the light has less value, because a lot of the ‘photon goodness’ has been taken out before it reaches them. This is why plants that will grow happily in open shade will grow less well in overhead shade.

Now, the shade from deciduous trees has some advantages, because in spring most trees are slow to leaf out, allowing much more direct sunlight through. In fall too, after the leaves have gone, light comes through, and in warmer, southern areas this is especially helpful in winter, where temperatures may be warm enough for plants to still be growing slowly. So a Thuja Green Giant, planted in the overhead shade from deciduous trees, especially in a warmer zone, may still do OK. It will certainly be a bit thin and more open, but with some trimming it should be possible to keep a reasonable look to it.

Types of Shade Three – Overhead Shade, Evergreen Trees

Now we come to the really difficult shade, the sort of thing you find underneath a big old spruce or fir tree, or a laurel bush. Not only are many evergreens very dense, allowing very little light through, but the shade is unrelenting, just as dense in fall, winter and spring as it is in summer. Gardeners know from experience just how few plants will grow in these conditions, especially if the branches are low and close to the ground. Here, Thuja Green Giant is simply not going to make it, so use something more shade tolerant, like Yew or Plum-yew (Cephalotaxus).

Types of Shade Four – Seasonal Shade

Most of us know that the sun is in the sky for longer in summer than in winter – pretty basic stuff. As well, the sun is higher in the sky in summer, especially between the two equinoxes, March 21 and September 21. Each day up until June 21 the sun is a little higher, and then it goes lower again, until everything turns around on December 21 and starts again. So if you look at your garden in winter you will see a lot of shade, from buildings and the long shadows of trees, especially evergreen ones. But as the shadows shorten, areas that were in shade are now in full sun, and this coincides with the growing season too. If you plant Thuja Green Giant in a spot that is only shady in winter, it will grow almost as well as in a spot that is sunny all year, because most of the growth happens between spring and fall, even though the plant is evergreen. If you want to know if you can make a hedge with this great plant, or plant a specimen or two, it is best to look at the available light during the summer period, as any shade in winter has very little effect.

Ah, I See. . .

It’s obvious that shade is a complex subject, and simply rules like ‘grow in sun’ have to be thought through in each garden, and the areas more closely identified. Then you will be able to plant more effectively and get ‘the right plant in the right place’. Hopefully that will mean that you can grow Thuja Green Giant in more places than you thought possible.

So you planted a hedge last fall, you have just planted one in the last few weeks, or you are about to do it very soon. Congratulations – hopefully you chose something tough and fast-growing, like Thuja Green Giant, or in colder areas, Emerald Green Arborvitae. In very hot, dry areas you perhaps went with Italian Cypress, but whatever you chose, what happens in the first year after planting will set things up for the rest of your hedge’s life. Let’s see what you can do – nothing complex you can be sure – that will give your valuable new hedge the best start in life.

Prepare the Soil Well

If you have already planted your hedge, then this may be advice too late, but if not, then three things are important:

Dig Deeply – try to prepare the soil as deeply as possible. Try to go down 12 inches, mixing the soil, and adding suitable materials. For a single tree, prepare an area at least 3 feet across, or a line 3 feet wide for planting a hedge row. If you use a roto tiller, these machines can fool you into thinking you have done a great job, while in fact they just went over the surface. Go over two or three times, working the machine slowly, and letting it sink into the ground as far as it will go.
Add Organic Material – it doesn’t matter much what kind, just as long as you add it. A layer 2 to 4 inches deep is usually best, and garden compost, rotted farm manure, rotted leaves, even lawn clippings and fresh weeds, are all good materials to incorporate into the soil. These increase the water-holding capacity of light soils, increase the drainage and air content of heavy ones, and add nutrients and valuable microbes too.
Add Phosphates – this nutrient, needed for root growth, doesn’t move into the soil from the surface for many years, so it must be dug in to be effective. Sprinkling it on top after you plant is completely ineffective. You can use bone meal, superphosphate, or triple superphosphate, it really doesn’t matter, so consider cost. Sprinkle a layer over the soil before you add the organic material. You can’t damage your plants if you use too much, and a solid dusting is about right, so that it is clearly visible.

Water Regularly

This is so important, and basic, that it cannot be over-emphasized. New plants only have the soil that was in the pot to depend on, and in warm weather, or when growing vigorously, they soon use that up. It takes some time for roots to move out of this limited space and explore the surrounding soil. So when watering your new hedge, don’t use a spray and water the top only. Use a gently rain head, or a slow-running tap, and soak down close to the stem of each plant, letting the water run deeply down. This will keep your plants happy. You do also need to keep the surrounding soil moist, to tempt the roots to spread out, and this is why many smart gardeners put a ‘leaky pipe’ watering hose – the black, porous kind – down along their hedge. Weave it in and out of the stems, and let it run for a few hours, until the whole area is thoroughly watered. It does a great job, and also saves you the trouble of standing their watering.

Fertilize with Liquid Fertilizers

Feeding hedges is important. Like lawns they get clipped regularly, so foliage is lost, and it has to be replaced. This means more nutrients are used than by an untrimmed plant. Granular fertilizers are the easiest to use, and the most cost-effective, but young plants don’t have big root systems, so they can’t easily access the nutrients from these materials, which need time to migrate down into the soil. Far more effective is a liquid fertilizer, that carries the nutrients right down to the roots with the water. Choose something designed for evergreens, which will have lots of nitrogen to stimulate rapid growth. These fertilizers come as concentrated liquids – the easiest to use – or as a powder – the most economical. The only issue is that because they are dissolved in water, they cannot be very strong, so you need to re-feed every 2 weeks to a month. But for the first year they really make a noticeable difference in the growth rate and foliage density of your new plants, making them sturdy and strong. Stop feeding in early fall, to allow your trees to slow down and toughen up for the coming colder weather.

Start Trimming When Your Start Growing

When creating a hedge, we want a dense, twiggy structure, with lots of tight branching, to give you the solid structure that makes the most private hedge, the best looking one, and the one that resists winter breakage too. The single biggest mistake when people plant new hedges is to let it grow until it reaches the height you want, and then start trimming. This never gives the best structure. Far better is to trim lightly and regularly from day one. As soon as you see new growth, snip off the end inch of it. This will encourage the dense branching you want. It will also allow you to direct the growth upwards, not outwards, so that you have a slip hedge. Don’t forget to keep the upper part narrow, to encourage plenty of growth lower down. Once it gets going, trim very lightly once a month from spring to mid-fall.

Try to keep the front flat, but sloping slightly inwards, and the top horizontal – you might need some strings and a level to get started. Don’t trim at the very end of the season, especially in colder areas, as soft, young growth can suffer winter damage. In the end you won’t reduce the rate of growth significantly, as your new hedge works its way up to your target height, but you will have a great hedge as a reward for that bit of extra work.

This might seem like a very easy question to answer – just check the hardiness zone listed for it, put your zip code into the USDA map site, and there is the answer – right? Most sources list zone 5 as the coldest place to grow Thuja Green Giant, which means it is considered hardy to minus 20 degrees Fahrenheit (approximately minus 30 on the Centigrade scale, for all you scientifically-inclined gardeners – odd isn’t it, that we use metric money, but then use an ancient European temperature scale everyone else abandoned many, many years ago?). So that should settle the matter, and there is nothing else to talk about. . .

What About Wind Chill?

At this point someone is going to say that we have forgotten wind chill, that factor that separates two days at the same temperature into ‘tolerable’ and ‘brutal’ because of a howling northerly wind. Wind Chill certainly affects us, but not plants. Why? Because wind chill is a measure of how rapidly heat is drawn away from our bodies, something which happens because we are warm-blooded. Plants, on the other hand, are not, and their internal temperatures are basically the same as the surrounding atmosphere or soil. Apart from a few plants that grow so fast in spring – mostly bulbs – that they actually generate enough heat to melt their way through the snow, all plants are at the same temperature as the air, so Wind Chill is irrelevant to them.

Winter Burn

Wind does affect plants though, and it adds complications to just how hardy a plant can be. The usual advice given to gardeners about growing plants at the limits of their hardiness is to find a ‘sheltered spot’ in the garden for them. This usually means south-facing and protected by hardier plants from cold northern winds. This advice is of limited value, because what evergreens need protection from in winter is dry winds – whatever their temperature and direction. You may have seen the leaves plants in summer shrivel and burn in hot, drying winds, but although direct sun may play a part, it is the dryness of wind that matters. We may feel a hot summer wind as dry or damp, but in winter all winds are relatively dry.

This is because the amount of water the air can hold increases with temperature. Yes, many people don’t realize that a cold winter wind is much, much drier than a balmy summer breeze. For example, at 100 degrees Fahrenheit the air can carry over 50 grams of water in a cubic meter. At 50 degrees that falls to less than 10, and at 32 degrees less than 5. By the time we reach minus 20, the hardiness limit for Thuja Green Giant, it holds just 1 gram of water. Larger amounts turn into dew, mist, fog or rain. Winter air is very, very dry.

How does this effect plants? Water is constantly being lost from the leaves and foliage of plants, by a process called transpiration. That water must be replaced from the roots, and when the ground freezes that cannot happen. So over time the foliage loses more water than it can replace, leading to drying, and the effect we call ‘winter burn’. In evergreens, this is the primary factor controlling hardiness. The other is the ability of roots to resist cold. Since soil is much warmer than the air, roots have much less cold-resistance than stems and branches. This is why plants left in pots outdoors die in winter, but the same plant in the ground will survive perfectly well.

What Does this Mean for Thuja Green Giant?

What all this means in the end is that if you can either increase the ability of the roots to take up more water, and/or reduce the amount of water lost from the leaves, then Thuja Green Giant can resist lower temperatures than usually suggested. Also, if you neglect these factors, it can easily die, even in zone 5. This is true for all plants, but especially for evergreens, which are vulnerable, because they carry their leaves into winter. From a practical point of view, this weakness is going to be worse in younger plants, so if you can keep your plants growing until they reach a good size, they are much more likely to survive in the long-term. So how about some tips for doing that?

Protecting Thuja Green Giant from Winter Cold

There are three ways to protect Thuja Green Giant, and other evergreens, from cold winter temperatures, especially when they are young.

Encourage Deep Root Growth

Deeper soil is warmer and doesn’t freeze. (How deep your soil freezes depends on where you live, of course.) The deeper the roots of your trees go, the more water they can continue to reach in winter, and the less their risk of winter burn. When you prepare the soil for planting, try to dig it as deeply as possible, so that the roots have plenty of soil to grow down into.

Water Your Trees in Late Fall

This is a very effective way to protect against winter damage. Let a hose run gently for several hours over the root zone of your trees, so that the soil is thoroughly wet. Do this as close to freeze-up as you can. Increasing the water content of the soil around the roots does two things. Obviously, it puts more water near the roots, so they can take up plenty. More subtly, it increases the specific heat of the soil, so it takes more winter cold to make it freeze. Specific heat is the amount of energy needed to change the temperature of something. It takes five times as much heat to warm wet soil as against dry soil. so that when the cold penetrates, we can think of it as being ‘used up’ in the top few inches, instead of freezing down a foot or two. The deeper roots can still get at liquid water and keep the foliage moist.

Mulch your trees

Besides its other properties, mulch is a good insulator. Soil covered with mulch, especially plant-based mulches, not stones, will freeze much less, and often not at all. Once you have completed that late-season watering, mulch around your trees too.

Use Anti-desiccant Spray

Widely used by professionals, but neglected by home gardeners, these products, which are entirely natural and made from an extract of pine trees, cover the foliage with a protective coating that reduces dramatically the rate of water loss. They have an equally dramatic effect on survival, especially helpful with new planting, and reduce or often eliminate winter burn, even on vulnerable plants at the limits of their hardiness.

So How Hardy is Thuja Green Giant?

You can see the picture is complex. The bottom line is that if you help your young trees in the ways suggested here, their survival is going to be greatly improved. In zone 5, and even into zone 4, your trees will leave winter as healthy as they entered it, and you can push the hardiness significantly – this is indeed a tough plant.

After a hard winter, it time to get out and explore the garden, to see how it survived, and if anything is needed. For hedges in particular, winter can be tough, especially if there has been heavy snow, freezing rain, or storms. As well, there are things to do that will give you the best results in the coming growing season, so let’s look at some things you can do that will fire up your hedge for a great season of growth and development. These things are especially important if you planted a hedge last year, in spring or in fall.

Check for Broken Branches

The weight of snow, ice, or simply strong winds can all break branches, especially on older hedges that have perhaps not been trimmed correctly. They may not always be obvious, although of course sometimes they are all too obvious! The main issue when removing broken branches from evergreens is that most conifer evergreens, like Thuja Green Giant, Emerald Green Arborvitae, Cypress, and others similar plants, is that they cannot regenerate from old wood. That is, branches that don’t have some green shoots on them. So hopefully leaving a thick branch, thinking it will re-sprout, as most trees do, is never going to work. If a breakage has happened below the green parts of the tree, then remove it neatly right back to the main limb it is growing from.

When cutting, leave the collar of bark you will see just where the branch joins on – don’t cut flush. The cut will be bigger with a flush-cut, and take longer to grow bark over, but more importantly, it is likely to cause die-back into the stem and leave permanent damage and weakness. This, by the way, applies to all limb removal from every kind of tree or shrub.

When you have cut away all the damaged parts you can assess your hedge. If you trimmed from an early age you should have lots of branches surrounding the gaping hole where that limb came out, and you will be surprised how quickly even large holes fill in. Smaller gaps will be gone in half a season, larger ones might take two seasons, but go they will.

If however the damage is to the end of a hedge – perhaps a snow-plough ran into it, for example – it is much harder to repair, and there it makes much more sense to take out the last tree entirely, dig the area well, and plant a good-sized replacement.

Mulch Your Hedge

If your hedge is young, or old and showing yellowing and slow growth, then mulch is very beneficial. Use something rich and nutritious, like garden compost or rotted animal manures (cow, sheep or horse) rather than bark chips or shredded bark. Yes, those hard materials last a long time, and they do conserve water and suppress weeds, but they don’t supply any nutrients. Richer organic materials release lots of nutrients as they break down, and for an older hedge they really will rejuvenate it over a few months. For young hedges too, the benefits are terrific, with better soil properties, more beneficial microbial activity in your soil, and nutrients too.

When mulching, keep the material clear of the stems, and don’t bury the foliage either, as it will soon die and brown if it isn’t exposed to light. A layer 2 to 4 inches deep in about right. You don’t need to remove all the old leaves and clippings which often accumulate under hedges, as they will also break down once you had some rich compost.

Fertilize Your Hedge

By far the most important thing to do in spring, especially for a young hedge, is to fertilize it. You can find both older-style chemical fertilizers, and organic-style ones too, and organic ones are especially useful for poorer soils, and of course they don’t involve energy-intensive manufacturing from fossil fuels either. To the plant it makes no difference – by the time they are ready to be absorbed by the roots they have been turned into basic elemental forms – plants don’t absorb vitamins or other complex molecules, since they make them all themselves.

There are three main kinds of fertilizers suitable for hedges – liquid fertilizer, granular fertilizers, and slow-release fertilizers. All three have their uses. Immediately after planting, and for the first season, you will get the best results using liquid fertilizers. These are sold either as concentrated liquids, or powders. Powders are much more economical, and easy to use – just dissolve the recommended amount in water. Young plants have limited root systems, and liquid fertilizers flow right down into the root ball, so they are easily and quickly absorbed, but they need regular application – once a month or even once every two weeks – for best results, as they cannot be concentrated, or the roots will burn.

In the longer term applying liquid fertilizers takes too much time, so after the first season or two, switch to granular forms. These are also more economical. The ordinary types are applied in early spring, mid-summer and early fall. Follow the directions for the amount to apply. Slow-release forms, which look like tiny pebbles, are more expensive, but they only need to be put down once a year. Choose which to use depending on your budget and how much time you have available. Fertilizer in sticks which you drive into the ground is usually not ideal, as it may burn the roots near it, and not spread well to areas further away, producing uneven growth.

Formulations

The fertilizer market is crowded, with many brands all competing for our attention. Forget all that, and instead go straight to the fertilizer formula – the 3 numbers (20-20-20, for example) required by law to be somewhere on the box or bag. If the first number is noticeably bigger than the next two, then that will be fine for a hedge. Even lawn food works on a hedge, although it is not ideal, since it has too much nitrogen (the first number) and not enough of the other nutrients. You want something balanced, but with more nitrogen than anything else. Other nutrients are optional extras, unless you have very sandy soil, where micronutrients can be scarce. If you mulch with that rich organic material we mentioned, then all you need is the nitrogen boost for rapid growth, so don’t worry about the fancy stuff. Check out our blog pages for more detailed blogs on fertilizing hedges.

Watering

In some areas early spring can be dry, with little rain. If that is happening, don’t forget to water your hedge deeply, especially a young hedge. A lot of the annual growth takes place in spring and early summer, and dryness will seriously reduce that, so don’t forget to water.

With spring arriving across the country – sooner in some places than others – planting time has arrived, and many people will be planting hedges and specimens of America’s most popular evergreen, Thuja Green Giant. This fast-growing tree is the top choice for taller hedges and screening, but when faced with that shipment of plant, sitting in their pots, some new gardeners may not be too clear on the best way to plant them, so let’s consider that. After all, getting plants off to a good start is always the first secret of success, and equally, a bad start can set you up for poor results, and even failure.

Prepare the Ground

Although we don’t see it, the life of plants below the ground is at least at important to them as what goes on above ground. Scientists have laboriously excavated the root-systems of plants from grasses to big trees, and in every case the roots occupy a vastly bigger volume than the above-ground parts. Many times bigger. So it follows that we should give it just as much attention, since we want to see much faster growth than a tree is nature will achieve. Most young seedling trees sprouting in the wild die, and those that don’t usually struggle for years to gain a foothold, but in gardens we want rapid growth and establishment from Day One. To do it properly you need two things when preparing the soil for your Thuja Green Giant plants – organic material and a source of phosphates.

Organic material

The exact type you use is not so important, but adding it is. No matter if your soil is sandy, clay, or something in between, the magic of organic material always improves any soil. Sandy soils retain more moisture and nutrients, and clay soils (which usually have lots of nutrients already) develop better drainage and more vital air penetration into the soil. You can use garden compost if you have it, rotted leaves, old potting soil from planters, rotted farm or stable manure, or even peat moss (which despite its popularity is not such a good choice). If you are planting a single tree, you need about a bucket full, and if it is a row for a hedge, you need a layer 2 or 3 inches deep, over an area 3 feet wide.

Phosphate

Of the three major plant nutrients (nitrogen, phosphate, and potash) you only need to add phosphate when preparing the ground. Why? Because this nutrient doesn’t move around in the ground easily, so if you sprinkle it on top it will quite literally take years and years to work its way down to where the roots are. All other nutrients are quickly carried down into the soil by watering or by rain.

There are several good sources of this, and most gardeners know bone meal. Expensive for a big job, its great for a couple of trees. Otherwise track down some superphosphate (or triple superphosphate, which is a bit stronger) and use that – it does the job at lower cost. A heavy sprinkling of this – like a light snowfall – should go down before digging, and in poor soil as some more as you go too. You can’t hurt your plants with too much, and it stays in the ground for many years.

Digging

Scatter the phosphates and then spread the organic material on the ground before digging or rototilling, which should then be done as deeply as you can go. For a row, prepare a strip at least 3 feet wide, or 5 feet wide if you are planting a double row. For an individual plant, dig an area at least 3 times the width of the pot, and again, go deep. Then level of the surface and leave it to settle for a few days before planting, if you can. If it was dry when you dug, setting up a sprinkler and giving the area a thorough watering is also a good thing to do.

Planting

Now to get down to the real job. The night before you plant, give the trees in their containers a good watering, soaking the soil. Never plant a dry tree, because it can be hard to get the root-ball wet after planting is over. Doing it the night before will mean it is not soggy on the day, and easier to handle than a freshly-watered tree.

You will have worked out the spacing for your plants, as we went into in detail in this previous blog, so set out your plants according to your plan. With hedges and screens, the best future look requires careful, even spacing, so put some time into adjusting this until you are satisfied. Use a stretched string to get the row straight.

If you have prepared the planting spot well you will only need to dig holes a little wider than the pot – just enough to be able to easily plant. Dig the holes where you have placed each plant, to the same depth as the pot only. Leave the tree standing next to each hole.

Preparing the Root Ball

Some people find the next step surprising, and hesitate to do it, because they are fearful of damaging the plant. Don’t be. This is an important step in helping your trees become established quickly and preventing future problems with roots strangling the growing trunk of your trees – a problem called ‘girdling’. It is similar to what you may have seen with trees tied to tightly to a pole – the rope cuts into the bark, and it can kill the tree. Roots wrapped around inside the pot can do the same thing as they and the trunk grow larger. Preventing this is important, so don’t be afraid for the tree.

Slide your Thuja Green Giant out of the pot. Take a sharp box-cutter and make 3 or 4 deep cuts from top to bottom around the root ball, going in about one inch deep. This will cut through the girdling roots.

Into the Ground

Now it is time to finish, and this is the easy bit. Sit the tree in the hole. Use a short stick laid across the top of the hole to adjust the position so that the top of the soil in the pot is level with the soil surface. Don’t bury deeply, and if your ground is poorly-drained, raise it up an inch or two above ground level. Now push back some soil, and using your foot, firm it down around the roots. Once you have about two-thirds of the soil back, fill the hole to the top with water. While it drains down, move on to the next tree. Once the water has drained away, put back the rest of the soil, firming it gently down. Rack the surface level, and you are done – no need to add more water, although if you want to you can.

To finish, mulch over the root balls with an inch or two or organic material, keeping it away from the trunk and foliage.

That’s it! You have given your Thuja Green Giant trees the best possible start for their life in your garden.

Deciding on the trees to use for screens and hedges is a big decision. Not only are these features going to set the form of your garden, and give you the privacy and protection you need, you will make a significant investment in them, so you want to get it right. Let’s look at why choosing Thuja Green Giant is going to be the right choice for almost all situations.

Why Choose Thuja Green Giant

For Fast Growth – 3, 4, or even 5 feet a year in the early years
For Year-round Green – stays green and healthy-looking all winter long
For Health and Vigor – its hybrid nature ensures super-vigorous and healthy growth
For Adaptability – grows well in many different soils and hardiness zones
For Easy Care – trouble-free, and after establishment takes care of itself

Choose Thuja Green Giant Because It Grows So Fast

The rapid growth of Thuja Green Giant, especially when young, has been proven in independent University trials. It grows faster than any other hedging evergreen we know off, adding up to 4 feet a year in the early years. Usually it will grow less the first summer after you plant it, although if planted in spring and cared for it will often be well established by the first fall. It is in the 3 or 4 years following that period of establishment is when you will the fastest growth, with your plants adding 3 or 4, or in exceptional circumstances even 5 feet a year.

This means that in those first few years, when you are anxious for the promise of privacy and screening to actually happen, Thuja Green Giant delivers. By the time you have had your trees in the ground for five years you can realistically expect them to add 10 feet or more to the height they were when you planted them. After that, growth with slow down, and adding two feet a year, and later just one, is normal. This is great, because by then your plants will be the size you want them, and slower growth means less trimming is needed.

Speaking of trimming, for screening you don’t even need to do it, although an occasional shaping helps keep your trees extra neat. Unlike many other fast-growing plants, Thuja Green Giant doesn’t begin to fall apart in a few years. Instead, it stays dense and tight, resisting wind, snow and storms, and always looking great.

Choose Thuja Green Giant because it is always Green

A common issue with a lot of evergreen hedges is discoloration in winter. A hedge should be fresh and green, but a lot of the plants used can and do turn bronzy-brown in winter, once some serious cold arrives. Yes, they do green up again in spring, but it does mean that they look dull and even unsightly in the winter months. At that time we want to see something green, to keep our hopes up for the coming spring. This is where Thuja Green Giant stands out from the others. It really does live up to its name, and your plants stay green and lush throughout the coldest parts of the winter. We don’t know about the ‘Jolly’ part, but the ‘Green’ part is certainly true!

Choose Thuja Green Giant for Health and Vigor

The last thing we want in our gardens is problems with hedges. They are meant to stay in the background, look good, and need limited attention. This is not always the case with some of the plants used. For example, older plantings of Leyland Cypress have been attacked by diseases in some areas, and other evergreens can also suddenly decide to start dying. Thuja Green Giant became so popular so quickly precisely because it stays healthy, and it keeps growing vigorously in many different locations and soils. It grows well in all kinds of soil, from sandy soils to clay soils, and in everything in between. It doesn’t like to be growing in soil that is constantly wet, but even then, if you plant your hedge or screen on a raised ridge of soil, up to 12 inches above the surrounding soil level, it will grow well in difficult, wet sites too.

It is also remarkably pest and disease resistant, because it is a hybrid plant, and plant breeders have known for years that when we cross two different species or forms that are related, the resulting plant is tougher and more vigorous than either of its parents. They call this ‘hybrid vigor’, and Thuja Green Giant has it in spades.

Choose Thuja Green Giant for Adaption to Different Locations

When planting hedges and screens, we don’t want plants that are choosy about where they live. With Thuja Green Giant we don’t have those problems. It is hardy all the way from zone 5 to 8, and even into zone 9 in drier climates. You might live in the rainy north-west; the hot and humid south- east; the colder north-east; or all across the open mid-west. It really doesn’t matter to this tree, because it is vigorous and adaptable enough to thrive almost everywhere. North America has an enormous range of climates, but growers in almost all of them tell us that Thuja Green Giant is thriving there. Even in coastal areas this is one of the best choices for everywhere short of right on the beach, because it is more salt-resistant than other arborvitae (Thuja) trees are. So no matter where you garden, you can be pretty sure that this is the best plant to choose.

Choose Thuja Green Giant for Easy Care

Finally, we don’t want to be fussy about our hedges, and they should not need a lot of regular attention. Thuja Green Giant doesn’t. It is of course best to give it some TLC in the first year or two, paying attention to watering it regularly, planting it into well-prepared soil, and using fertilizer to maximize the growth during those critical early years. Regular trimming right from the beginning is recommended too, for a hedge, as that builds a strong internal structure that will keep it healthy and lush right to the ground for life. But after that small push in the early stages, Thuja Green Giant, like children we have raised successfully, can stand on their own feet from then on, and really only need to be trimmed once or twice a year, depending on how neat or natural you want your planting to screening to be. You can see from all this, that for all the right reasons, choosing Thuja Green Giant is the right choice for almost every garden, almost everywhere.