Lemon trees in Containers Need Repotting

Q. I have two lemon trees, both about three feet high, in containers. My Myers lemon is about 10 years old but leaves get fewer and fewer producing only three lemons last year. When is a good time to repot it? 

A. Citrus does better in the ground than in containers. Extra management and care is needed when grown in containers. Containers allow more flexibility in freeze protection but trees growing in them are difficult to irrigate properly.

Newly planted 5 gallon citrus in 24 inch box. Box containers are good for a couple of years before they begin to fall apart and no longer hold water.

The usual reason for poor fruit production in citrus, particularly Myers lemon, is freezing temperatures around bloom time or shortly after. They like to bloom in January and February when freezing temperatures still occur. It only takes a light freeze to kill flower blossoms that are unopened, opened or small fruit that has just formed.

Be careful of soil mixes added to containers. Some soil mixes are not very good. Pick a soil mix that has a good reputation, not the cheapest one on sale.

A good time to re-pot them is now. Lay the container on its side and gently pull the plant and its root ball out of the container. Wash the inside of the container thoroughly.

With a spray nozzle, wash some of the soil mix from the root ball. Remove about one quarter of the roots with a sharp and sanitized pruning shears.

Look at the roots and see if they are healthy. The newest and smallest roots should be a creamy white color.

Slide the plant back into the container and push both upright. Locate the plant and root ball in the center of the container and add fresh container mix. Adding water with a hose will wash the soil mix into voids and remove air pockets. Gently lift the plant so that soil can wash under it and elevate the plant to the same depth it was previously.

Fertilize the plant with a fertilizer suitable for citrus. A rose fertilizer or fruit tree fertilizer will work if you can't find a citrus fertilizer.