As spring slides into summer, those who didn’t do everything they planned for spring start to worry. Is it now too late? Will I have to wait until fall or next spring to do that planting in the garden? Specifically, I am planning to plant a screen or hedge of Thuja Green Giant – am I now too late?

The traditional planting seasons of spring and fall were connected to the traditional way that plants were grown in nursery fields. When they reached a saleable size, they were dug and usually wrapped in burlap, or put into temporary pots, before being sold and then replanted. These things must be done at the right seasons, and trying to dig and plant in summer was something doomed to failure, because a large part of the active root-system is left in the ground.

Nursery methods have changed a lot, and today plants like Thuja Green Giant are grown for most or all their lives in pots. This means there is no root disturbance when they are moved around, and they arrive at your home with 100% of their root system intact and healthy. So the simple answer to planting is that today we can plant almost all year round, as long as the ground is not frozen. There are some good reasons for not planting in the depths of winter, but the situation for summer is much easier. Summer planting is not only possible, but easy and successful, as long as you take some simple precautions. Let’s see what those precautions are, and then you will be ready to plant that screen or hedge you have been planning – no matter what season it is.

Tips for Summer Planting

  • Prepare the area well, and water it thoroughly the day before
  • Be sure the plants have been water well before taking them out of the pots
  • Water deeply when planting
  • Mulch the root-zone to reduce water loss
  • Water close to the trunk every second or third day for the first weeks

Preparing the Planting Site

Just as for any other season, preparing the ground for planting should be top of your list. Most failures can be traced back to poor preparation. Digging a pot-sized hole in hard ground, and then pushing the plant into it, is always going to give bad results, even for tough plants. Instead, dig the whole row you are planting in, to a width of at least 3 feet. Incorporate plenty of rich organic material, to hold water and feed your plants.

If the ground is dry it may be hard to dig, so you should water the day before you dig or till. Once it is all ready to go, water thoroughly again the evening before you are going to plant.

Preparing the Potted Plants

When your new plants arrive, you may not be ready to plant right away. Remove all the packaging, and then place the plant in an area shaded from the afternoon sun. Plastic pots, especially black ones, absorb a lot of heat from the sun, and this damages the roots. If you do have to leave the plants in the sun, arrange them in a block so they shade each other, and then put something over the pots on the south and west side to protect them from direct sunlight. Burlap, some broad planks, mulch or loose soil are some possible materials you could use.

The biggest risk when planting in hot weather comes from handling plants with dry root balls. The soil can fall off, the roots rapidly become desiccated once outside the pot, and there is a real danger that the root ball will still be dry after you have planted and watered them. So always water the pots thoroughly the evening before planting. If you have to water them just before planting, go ahead – the only problem with that is the soil is wet and so makes more mess.

Water Deeply When Planting

You should still cut through the circling roots around the root ball in two or three places – it doesn’t hurt, and it encourages the roots to grow outwards, which is what you want. The commonest way people plant is to fill the holes completely and then water the area. A much better method, especially during summer weather, is to put back half to two-thirds of the soil, firming it down around the root ball. Then fill the remaining space with lots of water, and wait until it soaks down. This simple trick makes sure that plenty of water is available around the roots, where it is needed, not in the top few inches, where the roots can’t reach it. If you are forced to plant into dry soil, then do this soaking twice, so that the water spreads outwards too. Once the water has drained away, put back the rest of the soil, and once all the plants are in, go around and give them a final soaking.

Mulch the Root Zone to Conserve Moisture

Applying mulch over the root-ball zone of newly planted trees is always the right thing to do, but even more so in summer. It will keep the soil cool, which encourages root growth, and it reduces water-loss from the soil surface, reducing the risk of the soil drying out. Cover the soil further out than the width of the root-ball, because you want to create a cool, moist environment that the roots will want to grow into. Apply a layer 3 to 4 inches thick and keep it a few inches away from the stem and foliage.

Keep up the Watering

The biggest risk with summer planting is the rapid drying of the root-ball because of high rates of water loss from the foliage. Warm weather encourages growth, and it also increases the rate that water is lost from the leaves, especially from soft new growth. The only water available to newly-planted trees is in the soil that the roots are in, which is a small volume. So that moisture can be removed in a day or two. Water will be drawn into that soil from the surrounding earth, especially if you have firmed it down properly, but it may not happen fast enough. Because you see the soil surface looking damp, that doesn’t mean the hidden root-ball is. For the first three or four weeks, water every second or third day by letting water trickle down close to the stem of each plant. That way you will keep that root-ball damp. Water the surrounding soil too if it starts to look dry, because you want the roots to grow outwards, and they won’t grow into dry soil. Once the plants are established, you only need to water the whole area, as normal.


If you follow these simple tips, which are just good gardening habits, then summer planting of Thuja Green Giant is as easy as relaxing on those gorgeous summer days and watching your plants grow.