Many circumstances can cause falling leaves on a citrus tree. One is overwatering. A second is adequate watering, but poorly drained, or saturated soil. Also, some pests or diseases may cause yellowing leaves that fall away, such as aphids, canker, or some fungi. Finally, it is possible that a lack of nutrients is causing the falling leaves.
Don’t deprive your citrus tree of nutrients! Shop Yarden’s collection of soil, fertilizer, and care kits to ensure your plant thrives through many seasons.