My dwarf lemon tree is inside for the winter in a very sunny window that gets morning and afternoon sun. I have been fertilizing on a regular schedule, but recently it dropped all of its leaves and now the branches are starting to turn brown. I have dug into the soil and it doesn't appear to be too wet. I know that citrus is very sensitive to over watering. It has not been repotted in several years - does it need a soil change?
Dwarf Lemon Tree Lost Leaves
Certified GKH Gardening Expert
It is fairly normal for citrus plants to drop leaves during the winter indoors, since it's hard to give them as much light indoors as they get outdoors. However, if the branches are turning brown, there could be a problem.
One possibility is fertilizer buildup in the soil- this could happen if you have been fertilizing more often than recommended or if the water is not allowed to drain freely from the bottom of the container. Citrus trees should be fed half as often in winter as in summer. If you suspect this, wash out the extra fertilizer next time you water by letting plenty of water run through the soil and out throught the drainage holes.
Also check for any insects or other pests that may be on your tree.