e-mail Jane Owen with your gardening questions: jane.owen1@timesonline.co.uk

I haven’t cut back my lavender for a few years and it has become ‘leggy’ (my wife’s term) or ‘attractively gnarled’ (my term). My wife says I must replant but I want to leave it as it is. She says it will die if I leave it. Can you referee this domestic ding dong please? Jas Jones, Wimbledon

Certainly not – all I’ll say is that you can play it either way. If you leave it, it will eventually die (everything does) at which point you can replace it. That way you both win, don’t you?

What is the best way to compost – there seem to be so many ways to do it and although I’ve tried following Bob Flowerdew’s advice our heap doesn’t seem to rot down much. Amy Littlejohn, London

This September the National Trust is running a compost day in Sussex. If you can’t wait that long the organic gardening organisation Garden Organic has permanent composting displays for every type of garden and so does the Alternative Energy Centre in Wales which incidentally makes a great day out especially if you have children. Layering and pee-ing have always worked for me. Now that I have a small inner-city garden I use a wormery and an em-powered system (check it out at Wiggly Wigglers)

How can we get a fast evergreen hedge that will shield our garden from the eyesore garden next door (it is untidy and full of coloured playground equipment). We need it to grow to at least 3 metres. Name and address withheld

You may have problems with this because any evergreen hedge over two metres high comes under new hedge legislation. This means that neighbours have the right to make you cut the hedge back to two metres. Anyway, so long as you know that, you could use: leylandii (never let it grown taller than you want and it will stay compact and attractive); laurel; privet (it rarely drops its leaves in winter unless you live somewhere very cold) or yew. The latter grows about 300 cm a year if it is planted into well prepared, compost-heavy holes

We have had to remove a flowering cherry tree along our boundary because it was planted about 10 feet from the house and the roots were getting too large; it was about 15 feet tall. There is now a big gap and we feel rather exposed to view from the footpath on the other side of the boundary fence. Is there anything we can plant to fill the gap which will not pose a threat to the foundations? A Slee, Milton Keynes

This may sound an odd suggestion but a Cordyline might do the trick. They can get up to ten metres and they have the advantage of making dense screen without taking up too much root space. They have fibrous roots plus one or two roots which go straight down rather like a tap root. An alternative could be some attractive trellis (sturdy custom made stuff rather than the flimsy off-the-shelf product) painted with an attractive water-based preservative paints - Sea Grass from Cuprinol is my favourite. You could then grow an evergreen climber up the trellis.

I would be grateful to receive any help offered concerning my sheltered small south west facing garden. Two years ago an established Pyracantha bush shed nearly all its leaves, which grew back. The problem has spread to other plants and trees in the garden. Acer, roses, Betula albo-sinensis are all affected. I spray the roses, which show black spot and wonder if the problem is related. There isn't any sign of disease on the affected trees and plants and the foliage comes back. I am continually collecting the dead leaves. As the problem is extensive and ongoing I am unable to control it. Do you have any suggestions, apart from digging out and replacing? Your comments are most welcome. Regards, Jackie Taylor.

The fact that it is happening to a range of plants and you do not mention any sign of pest or disease makes me think this may be a drought problem. If your garden is sheltered it will be sheltered from rain. And the dry spells we have been having could well have the effect you describe. Can you install a water butt and make sure the garden is well watered during drought? Also, it might be worth beefing up the moisture-retaining properties of the soil by adding plenty of mulch – this should be done AFTER you have soaked the ground. Otherwise you will be sealing in drought.

I would like to suggest a neighbour’s garden to open for the Yellow Book charity. She has been working on her garden for over 20 years and it deserves to be publicly recognised. How should I go about including her in the NGS garden selection, please? Name and address withheld

Appearance in The National Gardens Scheme’s Yellow Book indicates an excellent garden of one kind or another, and it helps contribute to an excellent charity. County organisers (listed in the book) make the decision about which gardens should be included BUT, before you go ahead and contact him or her, a word of warning. Opening your garden to the public is very hard work, however good your garden. It can also be a bruising experience (most visitors are delightful but some are rude or thoughtless and some are thieves). Therefore you must talk to your friend about your kind idea before you contact the county organiser.

Honey fungus has killed off a lilac at the centre of our main bed. It needs another large blue flowered shrub but I can’t find one that is honey fungus resistant. Tim Carrington, Warwick

I have just returned from Hidcote garden in Gloucestershire where head gardener Glyn Jones has a similar problem. He is going to replace the affected trees with ceanothus. My favourite is ‘Trewithin Blue’ but you need to have a sheltered spot for it.

Our greenhouse has a layer of builders’ dust over the outside. I am unsteady on my feet and do not want to try washing it from a stepladder. We have tried spraying it with the hose but it hasn’t made much difference because the glass needs to be washed I think. Ted Lister, Sheffield

If there are two of you one could spray the glass with the hose while the other uses a soft-headed broom or even one of the telescopic window-cleaning tools available in most DIY stores. Otherwise you can buy telescopic broom jets, like this one online.

e-mail Jane Owen with your gardening questions: jane.owen1@timesonline.co.uk

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