What is ‘big bud’ on blackcurrant bushes?
Can I move a corkscrew hazel?
Phil Rhodes, by Facebook
Stefan says: The corkscrew hazel, or Harry Lauder’s walking stick, Corylus avellana ‘Contorta’, is a form of filbert with contorted and twisted branches. You have one that was bought for you as a birthday present 20 years ago and you would like to take it with you when you move house. It spent its first 10 years in a container but is now in the open ground and about 2.4m tall. Is it worth the risk, you ask, of trying to move it so that you can take it with you when you move?
Yes, I think it is, especially at this time of year. Soak the soil around it, lift it with as big a rootball as possible, wrap it in netting and hessian to minimise disturbance and take it swiftly to its new home where you should already have prepared a large hole with compost and bonemeal. Firm it in and water it thoroughly.
Marianne Richmond-Hale, by email
Stefan says: Big bud is a common problem on old blackcurrant bushes. The buds become swollen and rounded and fail to develop normally. It’s caused by the blackcurrant gall mite but the direct damage to the buds is less important than the secondary effects that result from the mites carrying a virus-like problem called reversion disease. This causes a decline in plant vigour and yield, which at first is barely noticeable. There’s no cure and once big bud is seen, the bushes should be replaced with healthy new plants, ideally on a different site. Generally, seven or eight years is the average productive life of most blackcurrant bushes before big bud and reversion take their toll and they need replacing.