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

I appear to have a bad attack of flea beetle in my first vegetable garden - the leaves of my pak choi, radish and rocket (though not lettuce) are peppered with tiny holes. What's a non-toxic yet effective way of getting rid of the blighters? Georgie Godby

My sympathies. Lacy salad may look interesting but it doesn’t give much of a feast. Worse still, the larvae of this infernal creature feed on the roots so further reducing the plants’ vigour. Unfortunately, there isn't a lot you can do about the problem at this time of the year apart from using something like derris dust although I’d still wash the leaves well before eating them. Next year, sow under fleece at a time when the crops will germinate and grow fast - and never let them get to dry.

I have bind weed growing within the boundary fence hedging between my neighbour and I. Can I spray Roundup behind my Lavatera but in front of my neighbour’s evergreen hedge without damaging either? Jo O'connor

The active ingredient of Roundup is glyphosate which neutralises on contact with the soil. This means that, so long as you apply the herbicide to the bindweed alone, neither hedge will be affected. Best to buy the paint-on type rather than the spray in this situation

Hi, I compost all my garden refuse and kitchen waste in a brick bay with wooden boards at the front and covered with old carpet... and it works, but not very well and also slowly. When I go to turn the compost I see literally thousands of wood lice but no worms - will they not co-exist, or - should I try to kill them? Colin Mapley

Sounds to me as if your heap is too dry which will encourage your woodlice plague and reduce your chances of having a speedy, efficient composting system. Woodlice tend to prefer dry conditions - they are part of the composting process so don’t get rid of them. They won’t harm worms but they will, in large numbers, sometimes eat seedlings and young growth. You’ll be able to reduce their numbers a little and make the heap more appealing to worms by getting the right balance of green and dry waste. It’s best to store up waste for a few days until you’ve accumulated enough to layer the heap: grass cuttings followed by a couple of layers of newspaper followed by vegetable peelings followed by some dry dead heads or an old pillow slip for instance. Then add an accelerator (urine is great, or you can buy an accelerator or make it from something like nettles soaked in water for a week). When the heap is neither too dry nor too wet, add some worms. They can be bought online form plenty of sites including Wiggly Wigglers www.wigglywigglers.co.uk . If you want to reduce the woodlice population as a whole you should clear away dead wood and any other dry, dark, decaying places they set up home, and encourage predators like toads.

I've just read your very informative article on growing vegetables, and wonder if you can help me with this. I would like to start a south-facing courtyard garden for fruit and veg. The soil here (Mid Wales) is awful heavy clay, and we've hard cored the area while some building was going on. If they are deep enough can I site my beds over the hard core? Also, will I have drainage problems with the beds and should I incorporate some sort of drainage hole at the base of the beds. Kaye Flack

You’d better add drainage holes to be on the safe side. So long as the beds are deep enough you won’t have to dig out the hard core which may help with drainage problems created by putting beds over heavy clay. Good luck!

Last week we purchased two standard orange trees which stand about 4ft tall to go in our newly constructed conservatory. However, I am now concerned that they are shedding their leaves at an alarming rate! The conservatory which is in a south-facing garden does become incredibly hot for the best part of the day. But with the sudden change to damp and wet weather, the temperature has dropped and this is when much of the defoliation has occurred. I have read that it is Ok to water regularly throughout spring and summer but in another source is says sparingly! Please can you advise on how best to keep these trees (Orange Citrus Sinensis) throughout the various seasons and to avoid losing any more leaves. Eve Canniffe, Reading, Berks

If it is really only a week since you bought the trees I would contact the nursery/garden centre where you bought the trees and ask for replacements. Having said that, citrus does not like sudden chances of temperature and will drop their leaves if they have to put up with extreme temperature changes, or with drought. They can be allowed to dry a little but not completely, their roots will not tolerate any water logging and they need regular feeding. You can buy citrus feed and citrus compost for a mulch (or repotting) from any garden centre. It’s also worth misting the leaves if the compost has become too dry.

We are planting an orchard and have already been given six apple trees which will take up half the space. We want to plant another six trees – not apples – and would appreciate some specific suggestions. The garden is warm and sheltered. Wendy Finer, Hemel

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