August 11, 2010
Generally, citrus don’t need pruning at all, they do however need a regular tidy up to control particular pest and disease problems. Also, if yours needs a good chop because it’s getting too big, there are a few things you need to know to guarantee a crop next year.
First things first, have a good look for any dead or diseased wood. It's useless and has to go. Just follow any dead material back to a healthy leader and make a nice clean cut there.
The other things to look out for are swollen bits on the stems – or galls. They’re caused by a tiny insect known as a gall wasp - the female wasp lays her eggs in the stem and that causes the swelling. If you leave them on the tree you can guarantee the new generation of wasps (due in spring) will reinfect the tree. When you get lots of these galls, they can really set your tree back so you need to get rid of them now. Just prune them off pop them into a plastic bag and throw it the bin. If you see any old galls with tiny pinholes in them, don’t worry about those. The wasps have already got up and left.
So what if your tree is getting too big and you want to reduce the size? What you don’t want to do is give it an all over hair cut, because you’ll remove all the flowers that are coming on now, which means you won’t get any fruit next year. The best way to reduce the size is to cut it back gradually. Just take out one or two of the longest branches this year and leave the rest behind to flower and fruit. Come next year, you pick another couple of branches to prune and so on. Over a few years you’ve pruned the whole tree and never sacrificed an annual harvest.