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

I've been growing some Tumbler tomatoes in hanging baskets and some dwarf beans in tubs, and I've just put them outside. All of them, including some trailing bedding plants that I've included with the tomatoes, seem to have developed some sort of blight. The leaves have developed a grey sheen and are dying. Have you any idea what could cause this? I have done nothing different this year from previous years, and they were looking very healthy a few days ago. The temperature has not dropped below 10 C since I put them outside. Thanks, David Ayre

Hi David, I wish you had said where you live. I cannot believe that the temperature has stayed above 10 C at night if you live in the UK. My guess is that a cold wild is the root of the problem. Having said that, it may be worth changing what you grow next year to avoid a build up of pest and disease.

My son lined his pond with puddling clay rather than a plastic liner. He was told this would give a more natural look to the pond, which is more to attract wildlife than to be a formal feature. Unfortunately, this has given the water a very cloudy appearance. Is there anything he can do to get the water to clear? Thanks in advance for any help you can give. Sheila Greenfield

Time is the best solution here, as it so often is in matters of gardening and life. It will take a while for the clay to settle. On the other hand, if the cloudiness is algae, your son needs to aerate the water by adding aerating weed, available from most garden centres or pond-owning friends. A circulating water pump with a waterspout and fountain will also help.

For the past 10 years, we have rented a house with a large garden, on which we have lavished care and attention, not to mention a considerable amount of money on new plantings. Out of the blue, we’ve been given notice to quit in September. My boss thinks we should leave the garden "looking like Paschendaele." This is a bit extreme, but I would like to move what I can. However, it's hardly the right time of year, is it? I certainly want to take all my old-fashioned roses, some small shrubs and some herbaceous plants, but will they survive being unceremoniously dug up in June or July and transferred to pots for an indeterminate length of time? And what about aftercare? Your advice would be much appreciated. Mrs. Jennifer Lane Corsham, Wiltshire

Oh dear, I so sympathise, but the Paschendaele approach sounds like hard work for no reward. I have moved house with a mass of freshly dug plants stuck in pots for six months, and they all survived – but I dug out the plants in November. You don’t have much choice other than to take cuttings of everything you can. Even if it is the wrong time of year for some of the plants, it’s amazing how cuttings will take, so long as you give them the right conditions and a little TLC. You could also dig out everything you want, making sure that you take as much soil as possible, so that the plant can’t tell it’s being moved. You’ll need some massive pots and a strong back!

For the past four to five years, I've had an irritating pest in my garden and can't find out what it is. It's a small fly that looks like a piece of yellow pilau rice with black wings. It loves my roses, and it appears to hang onto the stems and inject eggs into them. The stems then get brown furry wounds from which I think emerge caterpillars, which then eat every single leaf and get pretty nastily big. Spraying does kill them, but it's a challenge to keep up with the little blighters. I tend to pick them off and step on them, but I can't be there all the time. Thanks for any advice you can give. Melanie Jones

Your pilau rice pest is probably a rose leafhopper, and it really can be controlled by most insecticides, from fatty acids to bifenthrin. Good luck – they are a menace and you will not be able to stay on top of them by picking them off.

My garden is surrounded by a 6 ft fence. The clematis, ivy, etc. has now reached the top of the fence, but the mass of growth is still only halfway up. Should I cut the tops off to ensure that they bush out? At the moment, I trail them along the top wires, but they then get tangled in with the next clematis. Thanks in advance for your advice. Linda Hutson

On the whole, clematis won’t have much foliage in the first metre or so, and cutting them back at the top won’t make much difference. Most grow so enthusiastically that they smother neighbouring plants - apart from Ivy, of course, which smothers everything in sight and makes good growth from the bottom up. In other words, you’ve got a good combination of plants, so long as the clematis have enough space, and so long as you keep a close eye on the ivy, which can destroy fences and clematis. You may need to add some trellis to the top of the fence to give the clematis some extra growing space.

Hi Jane, My father- in- law has purchased a winter flowering cherry tree (Prunus subhirtella, 'Auntumnallis') for our rear garden. However, the garden is quite small, approximately 12 metres square with a large brick garage at one end and a large patio and house at the other. The sides of the garden are flanked by pathways, where there's a compressive 'mains sewerage drain system’ running under the garden. I have heard that flowering cherry trees can have invasive root systems and should not be planted anywhere near house foundations, drives, buildings and drains, as the potential for damage is high. Is there a rule of thumb calculation or a minimum distance involved? What small tree would be suitable to plant in a garden like mine? I would be very grateful for your advice as soon as is possible, as I anticipate my father-in-law will visit soon to plant the prunus. Thank You. Ron Titchener, Wivenhoe

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