Leaf Drop on Apricot Reasons Why

Leaf drop on any tree can happen if the flow of water from roots to the top is interrupted.

Q. We have a five-year-old apricot tree. Previously, it’s always seemed happy but this year it leafed out beautifully, then it started dropping its leaves. Apricots are still on the tree but not developed yet. Then this week ½ of the branches on one side are leafless.

Another angle of the same tree.

A. Pictures were sent to me of this tree so let me explain what I saw. The apricot tree is 6 to 8 feet tall with a similar spread but leaning strongly toward the light but away from some taller shrubs on one side. Leaves are on the ground and have dropped from the side away from the light. The week it dropped its leaves was a hot week and then it got cool again.

Apricot sap dripping from limbs or the trunk can be a sign of borers particularly if you see it when it gets hot.

            Trees drop their leaves because they are not getting enough water. They also drop leaves if it’s too dark, but I think in this case it’s a water issue. A lack of water can be from not enough water applied to the soil under the tree, borer damage in the trunk or several large limbs or a disease problem.

Sap dripping from the trunk can indicate wet soils. Add lots of water and then hold off watering until the soil has begun drying.

            I’m going to rule out the disease possibility because it is highly unlikely in the desert. Borer damage is a possibility except the leaves are dropping at the wrong time of the year and from half the tree instead of a branch. Borers cause leaf drop during the heat of the summer, June or July, frequently affecting an isolated branch or two. So, let’s rule out borer damage.

Wood chip mulch applied several inches think is good for fruit trees planted in desert soils but keep the wood chips a foot from the trunk for the first few years to prevent collar rot. Collar rot on fruit trees looks alot like drought.

            It is possible this tree had gotten larger and was not getting enough water. Along with a shortage of water, the distribution was not over a large enough area under the canopy to satisfy its roots. As trees get larger, they require more water distributed to a larger area under the canopy.

            To test this idea, use an inexpensive sprinkler on the end of a hose, connected to a mechanical timer at the hose bib or faucet. Put the sprinkler about 2 feet from the trunk of the tree and turn on the mechanical timer for two hours so it wets the soil deeply in an area about 5 feet in diameter. Do the same thing to the other side of the tree. Do this twice a week for the next two weeks and let’s see if the tree responds.

            If I’m right, you will see new growth coming from the limbs that are bare and where there are leaves, you will see new growth. If this is the case, increase the number and size of the emitters. Place one drip emitter scattered about every 2 feet under the canopy of the tree. The water should penetrate the soil about 18 inches deep after an irrigation.