Symptoms of an Overwatered Meyer Lemon
Grown throughout U.S. Department of Agriculture plant hardiness zones 9 through 11, the Meyer lemon (Citrus x meyeri) is a small citrus tree that reaches only about 10 feet in height. This variety is excellent for home gardeners since it is more winter hardy than most other citrus plants. The Meyer lemon tree does not produce true lemons, but the fruits are used as lemons and are very similar, though they are less acidic. Meyer lemon trees are fairly easy to care for but don't like wet feet and will have problems if overwatered. Know the symptoms of an overwatered tree and what to do to save it so you can once again enjoy homegrown citrus.
Symptoms of Overwatering
The leaves of an overwatered Meyer lemon tree will turn yellow. Sometimes the entire leaf turns yellow, but it is also possible that only the veins in the leaves will turn yellow. This can be a sign of overwatering or an iron deficiency, so look for other symptoms of overwatering to confirm the cause of yellow leaves.
After they turn yellow or brown, the leaves of a tree that is overwatered will drop to the ground. While some leaf drop is normal, excessive amounts of leaves on the ground can be a sign that the tree is getting more water than it needs.
Too much water will cause the skin on Meyer lemon fruit to split open and then drop off the tree. If your tree is covered with cracked fruits or if there are many cracked fruits on the ground around it, too much water is likely the culprit.
One way to determine if a tree is getting too much water is to dig into the soil around it. Soil that is dry on top may still be holding water several inches below the surface. Use a garden trowel to dig a few inches into the soil near the tree. If it is soggy or smells sour, it's holding too much water.
Saving an Overwatered Tree
The first step to saving an overwatered tree is, of course, to stop watering it. Turn off any automatic sprinkler systems or drip irrigation so that you have complete control over the plant's watering, with the exception of rain water. Drip irrigation is convenient but is known for causing an excess of both water and salt in soils.
Mulch helps block weeds but it also holds moisture in the soil. If your tree has wet feet, removing the mulch around it can help dry the soil more quickly. Mulching around citrus is not recommended as it promotes root rot.
A tree with waterlogged roots is more likely to be damaged by the chemicals in fertilizer than helped by them. Give the tree time to recover before resuming your normal fertilization schedule. When fertilizing resumes, The University of Florida recommends providing 1 cup of 21-0-0 fertilizer per year of the tree's age. Split the application into three even treatments given in February, May and September.
Move to Higher Ground
If your Meyer lemon is still very young and small enough, carefully dig it back out of the ground, create a mound of soil at the planting site and replant the tree. This small dirt mound will raise the tree a few inches and keep the tree on slightly higher ground. Be very careful not to damage the tree's roots while digging it up, and do so only if the tree is small enough to handle this way.
Tips to Avoid Overwatering
When planning and planting your garden, be sure to keep citrus plants away from annual plants and others that need a lot of water. Your citrus tree may inadvertently get too much water while you tend to the needs of these other plants. Keep the two separated so this doesn't happen.
Establish a Watering Schedule
Citrus trees planted in the ground need to be watered about once a week, though some trees can go longer. Lemons planted in outdoor containers need water once or twice a week, and plants grown indoors should receive about 1/2 gallon of water a week. Remember to reduce your watering in the winter when Meyer lemon tress grow more slowly. It is best to give the plants one deep weekly watering rather than several shallow ones as this encourages deeper root development.
Watering schedules will vary based on humidity levels, rainfall and soil conditions, so consider buying a moisture tester for your soil so you know when to water and when not to.