Never has the need to prune citrus trees been greater than it is this March, as we continue our lawn and landscape freeze-recovery.
Many people are wary of pruning citrus, because they think it will be difficult, or that they might damage the tree. Often, citrus trees are neglected and left to grow wild in the mistaken belief they will look after themselves.
I'll take a little blame on that, because I often say DO NOT prune fig trees. (People often hear only what they want to hear.) But figs are the exception. Citrus pruning is critical, because a lack of it causes fruit quality to deteriorate and quantity to decrease. It also allows certain diseases to infiltrate the tree. Some regular pruning is, therefore, necessary.
But you know me ... I like to make things easy. So, here are some easy-to-follow steps to guide you through the process. We'll look at when to prune, the essential tools, and how and where to prune to keep your citrus trees healthy, be less prone to disease, look great, and produce more good-sized, well-shaped and tasty fruit.
Except for lemon trees, all citrus trees normally need pruning only every two years or so. This year is a bit different, though, because of the freeze. So even if you pruned last year, you must do it again this year sometime between March and August. But it is best done before flowering begins.
Lemons grow more quickly than other species, so they need to be pruned more frequently to keep them within bounds and to make fruit picking easier.
In any event, all citrus trees should be inspected annually for any disease or infestation and abnormal growth. (See the note on suckers below.)
To simplify the task, you should have at least three important tools. First, heavy-duty gardening gloves to protect your hands from those trees that have nasty thorns. (I use my rose glove-style Bionic Gloves.) Second, a pair of good-quality bypass secateurs (hand pruning shears). They're necessary for the accurate and clean pruning of smaller branches and deadwood. And third, long-handled loppers ... to prune thicker branches. You might also want a pruning saw in case an extra thick branch needs to be removed.
Inspect the tree from all angles starting from low down on the trunk. First, identify the graft joint. That's the point where the growing shoot of the tree was joined with the rooted stem of a stock variety. It is usually found on citrus trees between one and two feet from the ground and looks like a slightly swollen lump, although it is not always obvious. Above the graft joint is where the main branches start.
Strong new growth starting from low down on the main trunk below the graft joint are suckers. They must be removed. Suckers are new shoots produced by the donor rootstock and will not be true to the variety of tree. They will often be extremely thorny, will grow strongly, but produce no edible fruit. They sap strength from the tree and will severely reduce fruit production, so it is very important that they be removed as soon as they are noticed. Use your hand pruning shears to cut them off as close to the trunk as you can get with a clean, vertical cut. If they are very thick, use the long-handled loppers. A vertical cut is essential to allow moisture to run away and prevent rot. That sort of cut also allows the trunk to heal and absorb the wound quickly.
Once all the suckers are removed, pruning the main canopy can begin. It is important that the center of the tree is opened to allow sunlight and air to penetrate. As you prune, walk around the tree several times if necessary to get different viewing angles of your work. Prune out any branches that cross in the center, and remove all thin, spindly twigs by cutting hard to the main branch. Also cut out any dead wood to prevent infestation by wood boring beetles.
You can prune quite brutally when opening out the center of the tree's canopy, leaving as few as three main branches to grow outwards evenly from the center with smaller fruit-bearing branches growing outward from them.
To keep the size of the tree in check to ease fruit picking, prune tall branches back to keep the height of the tree to below eight feet. All length-shortening cuts should be made at an angle where possible.
These easy-to-follow steps will simplify your pruning and protect the trees from disease and infestation, liberate them from strength-sapping suckers, encourage new, fruit-bearing growth, and ensure better quality fruit from healthy, good-looking trees.
Now here's the kicker: You really need to remove the blooms this year and next on most citrus trees to ensure the best production from year three onward. (I didn't make up the rule.) If you purchase a tree this spring, please promise to follow that basic rule at the very least this year.