Ask Monty

Q When and how back shouldour ten-year-we cut old acer tree? Cilla Coote, Kent A I suspect your acer is a

Japanese maple

[pictured]. These should always be pruned in their dormant season, November-March, as they can be prone to bleeding when the sap starts to rise in spring. Prune sparingly to retain the shape, cutting back the longest or widest branches to the stem or a suitable junction rather than trimming it all over. Q Our compost bin’s wooden lid has rotted. Should we replace the lid or leave the compost open to the elements? Fiona Haley, Cleveland A In general compost bins do not need lids. Compost needs to be kept moist, but a lid can stop it becoming too wet. The compromise is to keep a board next to the bin that you can place over it to protect it from the worst of the rain. Q My jasmine bush is infested with mealy bugs. Any ideas how can I get rid of them? Valerie Todd, East Sussex A Hold off any feeding, particularly of a high nitrogen feed as this will promote soft, sappy growth that the little white bugs [inset] love. Next, buy some neem oil, mix 28ml of it with 4.5ltr of water and spray this on weekly. It repels, and restricts the growth of, many insects such as aphids and mealy bugs, but it won’t harm bees. Cold weather helps too – they hate it! Write to Monty Don at Weekend, Daily Mail, 2 Derry Street, London W8 5TT or email monty.don@dailymail.co.uk. Please include your full name and address. We regret Monty can’t reply to letters personally.