A Beginner’s Guide to Adding Trees to Your Garden
Are you a tree-planting virgin? Don't be intimidated, here's how to plant and care for your new specimens
Trees are the lungs of our planet, providing us with oxygen and storing carbon, as well as preventing soil erosion and providing homes to wildlife. Planting a tree is a rewarding experience and an extremely sustainable way to make a positive impact on the environment. Choosing the right tree can be quite daunting, but there is a lot of advice out there and some great tree nurseries. Read on for a short guide to planting and looking after your new tree.
This article is from our Most Popular stories file
This article is from our Most Popular stories file
How to plant a tree
…in the ground
Planting trees correctly will ensure years of enjoyment from the most wonderful life-giving plant. The correct depth is vital. Tree roots need oxygen and water in blended measure, and for this, they actually grow within the top metre of soil. This means when planting a tree, width is more important than depth. For this reason, the latest advice and planting method is to dig a square rather than circular area to plant in. The planting hole should be 1.5 times the diameter and not deeper than the rootball. Make sure you loosen any compacted heavy soil and remove any big material in the hole that may prevent root growth.
With container-grown trees, dig a hole no deeper than the roots. You can trim any potbound roots except for eucalyptus and magnolias, which don’t like root disturbance. With root-balled trees which are only available in the autumn and winter, try and plant them immediately to prevent the roots from drying out, otherwise heel them in to a temporary bed until you are able to plant. Check your soil when planting trees, as acid-loving trees will need extra ericaceous compost.
Staking a young tree is important to ensure the wind doesn’t cause any damage and disturb the roots. New roots need to develop and any movement must be limited. On that point, if you buy a tree and it is covered in hessian and wire, don’t be tempted to remove this; it can increase root damage. These materials will degrade in the soil over time naturally. Plant the tree as is, but you can remove the ties across the crown, as these will have been done for transportation only.
…in the ground
Planting trees correctly will ensure years of enjoyment from the most wonderful life-giving plant. The correct depth is vital. Tree roots need oxygen and water in blended measure, and for this, they actually grow within the top metre of soil. This means when planting a tree, width is more important than depth. For this reason, the latest advice and planting method is to dig a square rather than circular area to plant in. The planting hole should be 1.5 times the diameter and not deeper than the rootball. Make sure you loosen any compacted heavy soil and remove any big material in the hole that may prevent root growth.
With container-grown trees, dig a hole no deeper than the roots. You can trim any potbound roots except for eucalyptus and magnolias, which don’t like root disturbance. With root-balled trees which are only available in the autumn and winter, try and plant them immediately to prevent the roots from drying out, otherwise heel them in to a temporary bed until you are able to plant. Check your soil when planting trees, as acid-loving trees will need extra ericaceous compost.
Staking a young tree is important to ensure the wind doesn’t cause any damage and disturb the roots. New roots need to develop and any movement must be limited. On that point, if you buy a tree and it is covered in hessian and wire, don’t be tempted to remove this; it can increase root damage. These materials will degrade in the soil over time naturally. Plant the tree as is, but you can remove the ties across the crown, as these will have been done for transportation only.
…in a container
Trees that grow well in containers include: olive, bay, Japanese maple, fruit trees such as apple and pear, which can be grown as a cordon or espalier. You could also try, Pinus pumila ‘Glauca’ (dwarf Siberian pine) or Sophora microphylla.
Potted trees will dry out more readily than they would in the ground, so give container trees a boost by refreshing the top layer of compost in spring. Do this by gently scraping away the top 2 inches of old compost and replacing with fresh new compost, and if you think the tree would benefit, add a slow-release fertiliser in granular form.
Choose a container large enough for the rootball of the tree you are planting, making sure there are plenty of drainage holes and broken terracotta pieces to aid drainage. Plant your trees in a loam-based compost. Do not put a tiny tree in huge pot but instead pot up slowly in stages, increasing the size of the pot with every change.
Find a local garden designer or landscape architect to help with your project.
Trees that grow well in containers include: olive, bay, Japanese maple, fruit trees such as apple and pear, which can be grown as a cordon or espalier. You could also try, Pinus pumila ‘Glauca’ (dwarf Siberian pine) or Sophora microphylla.
Potted trees will dry out more readily than they would in the ground, so give container trees a boost by refreshing the top layer of compost in spring. Do this by gently scraping away the top 2 inches of old compost and replacing with fresh new compost, and if you think the tree would benefit, add a slow-release fertiliser in granular form.
Choose a container large enough for the rootball of the tree you are planting, making sure there are plenty of drainage holes and broken terracotta pieces to aid drainage. Plant your trees in a loam-based compost. Do not put a tiny tree in huge pot but instead pot up slowly in stages, increasing the size of the pot with every change.
Find a local garden designer or landscape architect to help with your project.
Position trees far away enough from your house
A lot of people are understandably concerned about trees growing next to properties, since tree roots spread outwards three times the height of tree. So do your homework before you plant one close to a property. Where you plant will depend on the tree type and the eventual size of the tree, its water intake and your type of soil.
With shrinkable clay soils, your property may be most at risk, especially during times of drought, as this causes the soil to shrink. Cracks will inevitably develop and this result can lead to subsidence and structural cracking in property. However, the tree roots are unlikely to directly penetrate solid footings, though buildings built before 1950 are the ones that tend to have problems, as these were built with far shallower footings.
Other issues with tree roots can be blocked drains and lifting of paving, which you can often see on pavements. Branches, too, can cause damage to roofs and guttering, so tree distance is important.
A lot of people are understandably concerned about trees growing next to properties, since tree roots spread outwards three times the height of tree. So do your homework before you plant one close to a property. Where you plant will depend on the tree type and the eventual size of the tree, its water intake and your type of soil.
With shrinkable clay soils, your property may be most at risk, especially during times of drought, as this causes the soil to shrink. Cracks will inevitably develop and this result can lead to subsidence and structural cracking in property. However, the tree roots are unlikely to directly penetrate solid footings, though buildings built before 1950 are the ones that tend to have problems, as these were built with far shallower footings.
Other issues with tree roots can be blocked drains and lifting of paving, which you can often see on pavements. Branches, too, can cause damage to roofs and guttering, so tree distance is important.
Water new trees carefully
How to water new trees once they’re planted is a frequently asked question, and the answer will depend to some extent on the type of soil you have. If your soil is sandy, you will need to water more than you would, say, with clay soils.
Once fully rooted, a tree will survive without watering. However, until a new tree has started to root fully, it will rely on you giving it a good watering, without waterlogging the soil. The best way to do this is by starting to water around the base of the trunk and slowly working your way outward to the surrounding rootball, making sure the water penetrates deeply into the soil. By watering this way, you will create a good damp circle around the trunk around a third larger than the diameter of the rootball. Water for up to an hour depending on the size of the tree.
If you have planted your tree in the autumn when the soil was damp, you may not need to water until the spring. And deciduous trees go dormant during the winter, so there is no need to water until the spring. If the winter is very dry, evergreen trees may need a bit of extra watering. During the active growth phase of trees in the spring and summer, demand for water will be greater, so keep an eye on them and remember that trees planted in exposed sites will dry out faster.
How to water new trees once they’re planted is a frequently asked question, and the answer will depend to some extent on the type of soil you have. If your soil is sandy, you will need to water more than you would, say, with clay soils.
Once fully rooted, a tree will survive without watering. However, until a new tree has started to root fully, it will rely on you giving it a good watering, without waterlogging the soil. The best way to do this is by starting to water around the base of the trunk and slowly working your way outward to the surrounding rootball, making sure the water penetrates deeply into the soil. By watering this way, you will create a good damp circle around the trunk around a third larger than the diameter of the rootball. Water for up to an hour depending on the size of the tree.
If you have planted your tree in the autumn when the soil was damp, you may not need to water until the spring. And deciduous trees go dormant during the winter, so there is no need to water until the spring. If the winter is very dry, evergreen trees may need a bit of extra watering. During the active growth phase of trees in the spring and summer, demand for water will be greater, so keep an eye on them and remember that trees planted in exposed sites will dry out faster.
Mulch, weed and feed
To mulch or not? That is a another common question. Once trees have been planted, you may get a lot of new weed growth. You can remove surface weeds (especially any grass) as soon as possible, because the grass around a newly planted tree will compete with it for any water. It is best, especially if planting in grassy areas, to use a strimmer guard where possible to prevent damaging the tree, and a tree guard if you have rabbits or deer around.
Using a mulch around the tree will help suppress weed growth. Put the mulch over the entire root area of the tree, which may well extend beyond the branches over time. Do not put mulch around the trunk as the resulting moisture will lead to bark decay.
New trees shouldn’t need feeding, since a slow-release fertiliser will usually have been added before you buy them. And you shouldn’t need to feed your tree once it is established. However, you can buy top dress slow-release fertilisers containing potassium for the autumn time if you think your tree would benefit.
To mulch or not? That is a another common question. Once trees have been planted, you may get a lot of new weed growth. You can remove surface weeds (especially any grass) as soon as possible, because the grass around a newly planted tree will compete with it for any water. It is best, especially if planting in grassy areas, to use a strimmer guard where possible to prevent damaging the tree, and a tree guard if you have rabbits or deer around.
Using a mulch around the tree will help suppress weed growth. Put the mulch over the entire root area of the tree, which may well extend beyond the branches over time. Do not put mulch around the trunk as the resulting moisture will lead to bark decay.
New trees shouldn’t need feeding, since a slow-release fertiliser will usually have been added before you buy them. And you shouldn’t need to feed your tree once it is established. However, you can buy top dress slow-release fertilisers containing potassium for the autumn time if you think your tree would benefit.
Know when – and what – to prune
There’s a lot to know about pruning, but in terms of key information, pruning trees is done for several reasons, and the timing will depend on why you are pruning as well as the individual species of tree. Be aware, however, that trying to prune a large tree to make it smaller is usually unsuccessful.
Here are some basics:
There’s a lot to know about pruning, but in terms of key information, pruning trees is done for several reasons, and the timing will depend on why you are pruning as well as the individual species of tree. Be aware, however, that trying to prune a large tree to make it smaller is usually unsuccessful.
Here are some basics:
- Winter pruning, or pruning when the tree is dormant, is the most common practice and will result in bursts of spring growth.
- Summer pruning is done to ‘dwarf’ the growth of the tree or direct the growth by slowing down branches you may not want.
- You can also prune to encourage flower growth. Prune spring-flowering trees after they have flowered but leave pruning of summer-flowering trees until the autumn or following spring.
- Try not to prune in the autumn as this will only encourage fungi and disease, which are easily spread at this time of the year.
Consider what to plant under your tree
It is always a challenge underplanting trees as the canopy will naturally shade underneath, depriving not only light but also moisture to any plants. However, some shrubs, bulbs and perennials will thrive with a bit of dry shade.
Here are just a few ideas to start with. Ferns, such as Dryopteris affinis the golden male fern, and Polystichum setiferum, the soft shield fern, do well. Bulbs such as Cyclamen hederifolium will look lovely as they spread in years to come, as will Anenome blanda, Scilla Siberica and the common snowdrop Galanthus Nivalis. Ground-cover plants such as Ajuga reptans and Euphorbia amygdaloides and Viola odorata (sweet violet) are good choices too. Perennials such as Epimedium and Pulmonaria will naturalise well in time. Hellebores can also be grown in deep shade under a tree.
It is always a challenge underplanting trees as the canopy will naturally shade underneath, depriving not only light but also moisture to any plants. However, some shrubs, bulbs and perennials will thrive with a bit of dry shade.
Here are just a few ideas to start with. Ferns, such as Dryopteris affinis the golden male fern, and Polystichum setiferum, the soft shield fern, do well. Bulbs such as Cyclamen hederifolium will look lovely as they spread in years to come, as will Anenome blanda, Scilla Siberica and the common snowdrop Galanthus Nivalis. Ground-cover plants such as Ajuga reptans and Euphorbia amygdaloides and Viola odorata (sweet violet) are good choices too. Perennials such as Epimedium and Pulmonaria will naturalise well in time. Hellebores can also be grown in deep shade under a tree.
Know about fruit-tree pollination
In general, fruit trees need pollinating partners, so if you plan on having a fruit tree, you will need another compatible tree in the same fruit species – but a different variety – to enable pollination, and to set fruit. This means that if, for example, you have a Cox apple tree that is flowering, another apple tree that is also flowering at the same time can be the partner pollinator as long as it is not a Cox.
In a small garden, if you only have room for one fruit tree, opt for a self-fertile variety of fruit tree. However, even self-fertile trees need to have pollen transferred from one flower to another and if there is bad weather that deters pollinating insects, so you may end up with a reduced fruit set. It is a good idea (anyway) to plant bee-friendly plants in your garden too.
In general, fruit trees need pollinating partners, so if you plan on having a fruit tree, you will need another compatible tree in the same fruit species – but a different variety – to enable pollination, and to set fruit. This means that if, for example, you have a Cox apple tree that is flowering, another apple tree that is also flowering at the same time can be the partner pollinator as long as it is not a Cox.
In a small garden, if you only have room for one fruit tree, opt for a self-fertile variety of fruit tree. However, even self-fertile trees need to have pollen transferred from one flower to another and if there is bad weather that deters pollinating insects, so you may end up with a reduced fruit set. It is a good idea (anyway) to plant bee-friendly plants in your garden too.
Choose evergreen for screening
In terms of good trees for screening, evergreens will of course work year-round. However, the position of even a single tree is just as important and can help block out anything unsightly, or neighbouring properties. Make sure, of course, that you plant considerately.
For good evergreens choose Ligustrum japonicum (privet), which you normally associate with a shrub but which also makes a great standard tree. It has dense, dark green foliage and will only drop its leaves if temperatures drop to minus 10 degrees. Ligustrums have the added interest of small white flowers in the autumn. There is also a lovely variegated form. Or you could try Photinia ‘Red Robin’, which has clusters of white flowers in the spring and bright red leaves that contrast with green foliage. Another good tree to try is Prunus laurocerasus (laurel).
Something to bear in mind with all trees planted against a fence line is that pruning will be easier if you get on well with your neighbour. So chat to them first and ensure the position of your new trees isn’t going to drive them mad because, for example, it is going to reduce sunlight into their garden.
Tell us…
Do you have any trees in your garden – or are you planning to plant one soon? Tell us all about it or share photos in the Comments section.
In terms of good trees for screening, evergreens will of course work year-round. However, the position of even a single tree is just as important and can help block out anything unsightly, or neighbouring properties. Make sure, of course, that you plant considerately.
For good evergreens choose Ligustrum japonicum (privet), which you normally associate with a shrub but which also makes a great standard tree. It has dense, dark green foliage and will only drop its leaves if temperatures drop to minus 10 degrees. Ligustrums have the added interest of small white flowers in the autumn. There is also a lovely variegated form. Or you could try Photinia ‘Red Robin’, which has clusters of white flowers in the spring and bright red leaves that contrast with green foliage. Another good tree to try is Prunus laurocerasus (laurel).
Something to bear in mind with all trees planted against a fence line is that pruning will be easier if you get on well with your neighbour. So chat to them first and ensure the position of your new trees isn’t going to drive them mad because, for example, it is going to reduce sunlight into their garden.
Tell us…
Do you have any trees in your garden – or are you planning to plant one soon? Tell us all about it or share photos in the Comments section.
Picking a tree for your garden can be a bit overwhelming but it’s worth doing your research so you don’t end up disappointed – don’t buy a tree on impulse!
Trees are often sold according to the girth size (circumference around the main trunk, 1m up from the soil level) and this is the indicator of maturity for any tree grown as a single trunk or standard.
And on that topic, there are also various forms of trees you can buy for the garden, including: standard, feathered, multi-stem, cordon, umbrella, box shaped, espalier, pollarded and pleached.