Start pruning your vines now, says Martin Fish
They’re now dormant so it’s the perfect time to start pruning
How time flies! It doesn’t seem five minutes since I was pruning my grapevine last winter. To keep a vine manageable and under control it needs pruning every winter, and the correct time to do this is when the vine’s dormant. In a cold greenhouse that’s from when the leaves fall in November to around February, but if growing in a heated greenhouse, the dormant period is a little shorter. The reason for pruning when dormant is because if you prune when the sap is rising, the wounds will bleed. For that reason, I like to make sure my vine’s pruned by the end of January at the latest, but I usually do it earlier. It’s a lovely job to get done over the Christmas holiday and it’s a good excuse to be able to get out into the greenhouse!
The aim with vine growing is to establish a framework of permanent branches, known as rods. You can have several rods per vine, depending on the shape and size of the greenhouse. I have one long rod trained the full length of the structure that’s supported on a wire below the ridge. Winter pruning is simply to cut back all the side branches that have grown this summer to one or two buds, so when finished you have the main rod with lots of short, stumpy spurs. In spring, new growth and flowers will develop from where you cut back to and through the summer these can be shortened after the fruit has developed.
On established vines it’s also a good idea to scrape off some of the flaky bark from the old wood as it acts as a brilliant hiding place for pests such as mealy bug and scale insects. Much of it will pull off easily, but if not use the blade of a penknife to get behind it and pull it off in strips.