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Trees

Here are the answers to some commonly asked gardening questions about trees.

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Last spring I purchased a young flowering cherry. The buds have never opened - is it dead?

If you mean that no leaves have been produced, then I think the answer is yes!

Some plants can take a while to get established, but this seems a long time for a cherry. The best way of telling for sure is to gently scratch the bark with your thumbnail; if there is green tissue underneath then the tree is still alive; if it is brown then it is dead. Start at the tips of shoots and work your way down until you know the extent of how much of the tree (if any) is still alive.

If it is dead then I would take it back to where you bought it and ask for a replacement. Most good nurseries and garden centres have a plant guarantee. Us gardeners never complain enough!

I have a tree stump sawn off at ground level which I would like to remove without digging. What is the best way of doing this?

Tree stumps that are still alive can be killed with SBK Brushwood Killer or Root Out. Make cuts in the bark and apply the chemical to these, as well as drilling holes in the stump and applying more of the chemical.

It will take several months to completely kill off the stump. If you want a quicker result you can use a machine called a stump grinder which will remove it in seconds. These can be hired from good hire shops or you could call in an approved contractor.

The easiest way of removing a stump is not to cut it down to ground level, but to leave several feet above ground. This will give you something to help lever out the trunk or you could tie a rope to it and drag it out; winches are also available to hire for such purposes.

Why haven't trees that I bought in the autumn taken very well? They were bought from the 'bargain basement' section of a garden centre.

It looks like the trees must have been seriously potbound before you bought them - many 'bargain' trees tend to be in this condition.

It would be better to buy trees that hadn't been sitting around in pots for so long or, better still, buy bare-rooted trees in the autumn.

Always tease out the roots of any container-grown trees or shrubs that look slightly pot bound. This is essential to ensure the roots are encouraged to grow out into the surrounding soil.

Also soil improvement is essential to ensure the roots get the encouragement they need to grow out into the soil.

We have a very large flowering cherry which has been happily growing and flowering for over 20 years. In Spring this year, we noticed that a part of the tree was very poorly leafed and consequently at bloom time that same part of the tree was poorly flowered.

This section of the tree has continued with poor leaf formation throughout this year and is seemingly the last part of the tree to now start shedding its leaves.

Examination of the leaves did show some leaf shot but probably no more than we have seen year after year. The tips of the poorly leafed branches do appear to have the tiny buds but in addition there is also some smaller offshoot branches that appear dead.

I am unsure whether we should be pruning this part of the tree or not. Any suggestions as to what might be the cause? The rest of the tree is in good health and did flower freely and was well leafed all summer.

It sounds like your tree is suffering from bacterial canker. This is a severe and destructive disease which may kill the tree in time. It has become much worse in recent years due to droughts and dry weather which have stressed and weakened the trees.

There are several symptoms that you will notice. First, is shot hole disease which produces small brown spots on the leaves. As the spots grow they fall out leaving a series of holes that look like the leaves have been hit by shotgun pellets.

The more serious symptoms are cankers occurring on the bark. At first they appear as shallow depressions bearing amber coloured gum, but later enlarge and exude large amounts of gum. Affected branches soon die back after yellowing or stunting of the leaves.

You could try pruning out affected branches - cutting at least 15cm (6in) beyond the dead wood and into sound wood; this should not be done now as the wounds are sites for further infection - wait until April . Unfortunately, there isn't a cure for bacterial diseases, but spraying with Bordeaux mixture in mid-August, two weeks later and again in October may help reduce the bacteria. But, more often than not, the tree will slowly die right back and will eventually have to be removed.

Bacterial canker affects both ornamental and fruiting cherries.

Only you will know whether the tree is beyond saving and whether it will need digging up and burning.

I have a Catalpa which is about 2m high at the moment, it has already been 'stopped' to make it form a pollard. I intend to keep it pruned to keep it small, but if I do this will there ever be any chance of it flowering?

Does it need older wood to flower or will the flowers come on the new growth given a warm enough summer? I live in Lincoln and the tree is in a small sheltered back garden where we do not get very hard frosts.

As we're always told - you can't have everything!

Hard pruning of catalpas in April is essential to keep the plant within bounds and to improve the size and colour of the foliage.

However, it will affect flowering. Having said that I have seen pollarded trees flowering very well. But it is essential that the weather is warm to promote flowering whatever you do, and it takes a few years for catalpa to get into a regular flowering mode anyway.

A close friend of mine has very recently lost her much beloved grandmother. She is very anxious to plant a tree in her memory - but doesn't know very much about gardening and has asked me to help her. I know a bit more - but not much. I would have thought now is not a good time to plant anything, but my biggest problem is that she wants to plant a tree that has the name May or Mary (or even Nan). To use a bad pun, I am stumped! I have tried to persuade her to get a rose or clematis where it may be easier to get one with the name she wants but she is adamant. Where do I look for the names of trees? Can you help? She lives in Sheffield, and she has a small but sheltered garden. I don't know the soil type.

Autumn through to early spring is a perfect time to plant a tree. The only thing that will stop you planting is if the soil is frozen solid or if it is waterlogged.

Hawthorns (varieties of crataegus) have the common name of May blossom - because that's when they flower - and would make an excellent choice.

I cannot find any other trees with any of those names.

I live in Pennsylvania, and will be receiving 10, bare-root, Japanese red maple trees that are approximately 60-90cm (2-3ft) high in the early spring (March or April). I don't want to lose these trees because of my ignorance. Could you please tell me what would be the best way to plant these trees to give them a head start in life?

First, I'd say make sure you plant them as soon as they arrive; depending on the weather I'd prefer to get these plants in during Feb/March. The only thing that will stop you planting is if the soil is frozen solid or if it is waterlogged.

Put the roots in a bucket of water for about 30 mins before planting to ensure they are thoroughly wet through.

Dig over an area of about a sq yd for each tree and incorporate as much well-rotted compost, manure or leafmould down to a depth of around 45cm (18in).

Dig a hole big enough to take the roots without bending them and deep enough so that when planted the trees are at the same level as they were growing in the nursery. There will be a mark on the stem to show this. Add some more compost and work this into the base of the hole.

Trim off any damaged roots.

Put a stake in the hole.

Plant carefully working a soil/compost mix in between the roots so there are no air gaps. Gently firm down with your heel. Attach tree to stake using two ties.

Water in thoroughly and keep the soil moist for the first summer.

That's all there is to it!

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Garden answers

Trees

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