My orange tree and lemon tree have lost a bunch of leaves this year. It started in the mid fall. Can you tell me why? I use a granulated citrus food every 3 months and they both are watered regularly except in winter wet months. Also, my orange tree continues to sprout with what I have been told to be 'suckers'. It was suggested to me to trim them away, as they disturb the development of the fruit. Then I was told that if I leave them alone, they will eventually produce and become an integrial part of the tree. Is any of this true, and if not, what would be best for my trees?
Certified GKH Gardening Expert
Typically, when a tree is putting out suckers, this is an indication that the tree is under stress. You should trim them away, as they will sap energy from the main tree and keep it from producing good fruit.
This combined with the leaf loss indicates that the tree is under stress. I would look to the roots as this is the most common reason for leaf loss. How long are you watering for? It is possible the water is not going deep enough into the ground so you may want to try watering less frequently but for longer periods of time when you do water. This will get the water deeper.
I would also have your soil checked by your local extension service. It could be a nutrient deficiency or it could be root nematodes (http://www.ipm.ucdavis.edu/PMG/r107200111.html) which only a tested soil sample would be able to tell you if either of these could be a problem.
Another possibility is that it is the trees have some sort of small pest, like aphids or scale. These can be hard to spot but can suck the moisture out of a tree, which can cause the leaf loss. I would treat the tree with neem oil (https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm). It is very effective with these pests and is safe for humans, pets and friendly bugs.
If the suckers are sprouting from below the graft of the fruit tree, it is coming from the more hardy root stock that your tree was grafted to. If that is the case, you may get some much less quality fruit, no fruit or even thorns on the suckers as they mature.