Feature tree

A strong vision and timely pruning provide the perfect result: dappled shade and a light, airy spot.

These trees create a “ceiling” for a garden room that helps to create a sense of enclosure. They provide protection from the summer sun while allowing maximum light in winter. They have a cooling effect on hot days, by the process of evapotranspiration – a benefit not provided by other options, such as a gazebo or sun umbrella. They drop all their leaves over a limited period, unlike evergreen trees, which drop leaves throughout the year. This allows for an easier cleanup.

Another benefit is that many of the trees available, such as melia, jacaranda, flowering cherries and silk trees, have an attractive display of flowers during spring. They provide food and a refuge for birds.

They also provide other landscaping options. I have an air plant (Tillandsia) growing on my patio tree; elsewhere in my garden I have other epiphytes, such as staghorn fern (Platycerium) and orchids, growing on my trees – part of my system of vertical gardens which I am enamoured with!

In some areas of my garden, away from my patio, I have native tree ferns and palm trees for shading over summer. I find with these that the leaf drop isn’t a problem, as I usually remove them from the tree with a pruning saw, and it is easier to clear away a handful of 2-3m fronds than thousands of small leaves! As a side note, I use these fronds as a coarse organic layer under my larger fruit trees, such as my apple and plum, as they are an excellent mulch and suppress annual weeds.

Getting back to deciduous umbrella-shaped trees, garden centres usually have plenty available, often in a range of interesting cultivars, and will have advice on which are most suitable for particular positions. Generally, the trees have been grown in containers, so can be planted at any time of the year, provided watering is maintained over the first summer. Some nurseries sell larger trees in bags, often with handles for easier lifting. These trees can be useful for providing an instant result. You may want assistance with carrying and planting these, as they can be heavy.

While appropriate trees are often chosen by gardeners, there is often little or no thought given to the care needed to develop and maintain a suitable shape. No tree will grow quickly to an ideal size and shape, and then stay put. When I walk around my neighbourhood, the majority of shade trees have got poor form, or have grown far beyond a suitable and manageable size. Sometimes, they have sent out branches close to ground level, crowding out the space that they are meant to be shading. Just as for garden plants in any situation, patio trees need regular treatments.

I’ll use the jacaranda I have in my courtyard garden as an example. I took care during purchase to pick out a tree that had a single strong leader, rather than multiple or crooked stems.

After planting, I removed the side shoots to encourage a branching framework, from about 1.7m above the ground. Having a tall, skinny plant with branches only at the top tends to create a trunk that is weak and susceptible to be being blown over. So I put supporting stakes near the tree, about 150mm from the trunk. I loosely tied the tree to these. The reason for the distance and loose tying is to allow the trunk some degree of movement in the wind – this is what encourages the tree to develop a strong trunk so it can, in the long-term, cope with gales.

During the growing season, I periodically prune the branches around the crown. I mainly do heading cuts – cutting a limb to about 4-5 leaves – which causes the twig to branch out into multiple shoots – similar to the effect when we trim a hedge to encourage a dense habit. I usually do this twice over summer, but it it’s more of matter of picking a period of vigorous growth, rather than a calendar event. Occasionally, I also do a thinning cut – if a shoot has got too long for my liking, I might remove it totally to a weaker side shoot. This is a way of decreasing the vigour of the tree.

As a result of this regime, there is less likelihood of the tree lifting my pavers if it is kept compact. Even though my 900 x 600 x 50mm pavers weigh 70kg each, the roots of a tī kōuka (cabbage tree) in another area of my garden lift them effortlessly.

As you can see from the picture, the jacaranda has become a noteworthy feature in itself – lush, well shaped, and showing off its gorgeous fern-like foliage.

I was determined to keep my Mediterranean-themed courtyard bright and airy, and my management of my tree has allowed that. Even though I have kept the tree compact, it still provides a pleasant dappled shade, rather than a dense blanket of shade, such as might be cast by a large conifer or beech tree. 

When considering options for shading a patio or another outdoor living area, deciduous trees are a logical choice.