Ask John Stoa, Our Gardening Expert!

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Even the most experienced gardeners need a little advice sometimes… especially from a gardening expert! Our gardening guru, John Stoa, answers your queries.


Q. I notice that some of the grapes in my greenhouse have started to rot. How can I stop this?

Botrytis on grapes sometimes occurs when outdoor conditions are cool and damp. Do not overwater the soil and keep windows open to allow plenty of ventilation. Remove any excessive foliage and sideshoots.

Q. I heard that some fruit bushes need summer pruning. Can you advise, please?

Red currants benefit from pruning as this encourages the formation of the spurs that produce the fruits. Cut all sideshoots to a few leaves in mid summer, which will also let sun and air into the bunches and help to ripen and sweeten them up.

Q. My onion tops are beginning to bend over. Are they ready to lift?

Provided the bulbs have reached their maximum size, lightly fork up the rows to let them ripen up. On a warm, sunny day, lift them and lay them somewhere in the sun where they can completely dry off before roping and storing for winter.

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First baby beet pickings cropped. Ask gardening expert

Q. Another allotment plot holder said I was wasting good food when I picked my beetroot and discarded the leaves. Are these edible?

The leaves of beetroot are similar to chard and spinach and can be used for cooking in stir-fries or put in the juicer for a very healthy drink. They can also be added to beetroot soup.

Q. I love lettuce in my salads. Is it possible to grow them all year round?

Lettuce can be grown in succession to cover cropping from spring to autumn, and for the winter period use some of the hardier varieties such as Hilde, Valdor or Arctic King. Sow them in a sheltered spot so they can grow and maintain soft, edible, tasty leaves.

Q. The recent wet weather has affected my potatoes, but I don’t know if it’s blight or blackleg. What is the difference and what can I do about it?

Blight is a disease on the leaves, which get black spots that grow and affect the whole plant. The disease spores are airborne. Blackleg is soil borne, usually from planting infected tubers. The leaves wilt and the whole plant collapses. In either case, remove all infected leaves and tubers as soon as possible. Some new potato varieties such as Sarpo Mira have resistance.

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Hannah McLaren

I've worked at DC Thomson for six years! I began as an intern at My Weekly and The Scots Magazine, which was extended by a few months to help out at The People's Friend. I then covered maternity as Celebrity Editor for My Weekly, before I became Multimedia Journalist at The Scots Magazine. Currently I'm writing digital content across each title.