Perfect Potted Trees – Thuja Green Giant

Everyone knows Thuja Green Giant as a hedging or screening plant – probably the best choice around. But evergreens have many other uses in the garden, and one popular use for them is as potted trees. These green specimens are perfect for the corners of a patio, on either side of an entrance, or lined up along a walkway. With the right choice of pot, they will enhance almost any garden style. Italian terracotta pots look perfect in a formal garden. Modern concrete ones bring to life the most modernist and minimalist designs. Big half-barrels look perfect in a country garden. Yew trees are popular choices for this purpose, but they are slow-growing, and take years to develop good form. Laurel are sometimes used, but trimming has to be carefully done, as the large leaves look unattractive with cut ends. For a plant that will mature in just a few years, is easy to clip into a variety of forms, grows large enough to make substantial specimens, and survives cold and drought, with never a pest in sight, it is hard to go past Thuja Green Giant. Always bright green no matter what the season, and quickly developing a tight, dense structure with clipping, this great plant can stand tall in any garden as a beautiful potted tree.

Choosing the Right Pot

Your choice of pot will be dictated by the overall design and theme of your garden, as we have already mentioned. There are some things that you need to consider for any pot, whatever its design. These basics are:

  • Drainage – make sure the pot you choose, whatever its design or the material it is made from, has at least one large drainage hole in it. For large pots two or three holes is ideal. If you find the perfect pot, but it has no drainage, then it is possible to drill out suitable holes. Wooden barrels are of course no problem, but concrete and terracotta can be tricky. Use a slow-drill speed, and turn off the hammer action. Use a masonry bit and trickle water onto the hole as you go. Drill a guide hole with a narrow diameter drill, and finish with a larger one. If you can, drilling from the inside while the pot is bedded on some sand will reduce vibrations and prevent cracking. Take your time, especially towards the end, to avoid shattering, and you will soon have perfect drainage in any container.
  • Material – choose something durable. There are some attractive plastic or fiber-glass pots available, but if these are very light you may find tall plants blowing over. Place a couple of large stones or bricks in the bottom to add weight if you use a container like that. Terracotta is an excellent choice, as it ‘breathes’, and by losing water through its surface draws air into the soil. This is ideal for vigorous trees like Thuja Green Giant, and for long-term growing.
  • Size – Thuja Green Giant is suitable for creating larger potted plants – 6 feet or taller. You need a container large enough to hold such a plant, so choose something that is between 18 and 24 inches in diameter, and about the same depth. In pots of this size your trees will live for years happily, as long as you water and feed them correctly.
  • Soil – Never use garden soil for potting. It is too dense, and holds too much water. Instead, use soils designed for outdoor planters, which are often available at garden centers and hardware stores. If you can’t find one, then use regular houseplant potting soil and add 15 or 20% composted bark, or shredded bark, like that used for mulch. This will open up the soil so it drains well, and also reduce shrinkage. Some gardeners add a little garden soil too – perhaps 10 or 15% – which helps the soil last longer and adds stable nutrients. This is not essential, but if your garden soil is rich and fertile, adding a little is worthwhile.

Taking Care of Thuja Green Giant in Containers

Thuja Green Giant is almost as easy to care for in a container as it is in the ground. A little attention will go a long way to keep your plants in top condition and looking their best.

  • Watering – this of course is the most basic attention needed. The rule is simple – water only when the top few inches are dry, and always water thoroughly until a little water flows out of the drainage hole. That’s it. Simple. In hot weather this might be every few days, while in the winter, waterings could be a couple of weeks apart. Let the soil tell you what to do, and never just give a small amount.
  • Fertilizer – the big difference between plants in pots and those in the garden is in fertilizing. Potted plants should be fertilized regularly, and a liquid fertilizer is best. You can also use slow-release granules sprinkled over the top of the soil. These release some nutrients every time you water, and one application can last all season. Whatever you use, follow the directions carefully. The season for fertilizing runs from early spring to early fall, and use a product designed for evergreens, such as a hedge food.
  • Pests – the simple answer here is that you almost certainly won’t have any if you are growing Thuja Green Giant. It is such a tough plant that insects and diseases leave it alone.

Trimming Thuja Green Giant

The wonderful thing about using this plant for containers is how quickly it will grow into the shape you want. You can create any simple geometrical form easily – straight or tapering columns – round or square; pyramids; large balls; or whatever your imagination suggests. The ‘secret’ to trimming is to trim off small amounts at a time, and do it regularly. While a big hedge can perhaps be left for a while, and will quickly recover from a hard trimming, you want your potted trees to look their best at all time, so ‘little and often’ is the key. This will create beautiful green surfaces of dense foliage, and give you the look you want. Always use sharp tools, and remember that hand-shears will give you the best control with something relatively small like a potted tree.

 

If you have been looking for suitable evergreens for large containers, to decorate your garden, or for a courtyard or terrace, Thuja Green Giant might not have been your first thought. But such a fast-growing plant is ideal for this, because it will very quickly develop into the shape you want – much more quickly than other evergreens will. Because it is in a pot, once established it will slow in growth, so you can easily keep it the shape and size you want. For the perfect all-year-round green column, it should be your first choice.