Why Is My Ficus Tree Losing Leaves?

If you're growing a ficus tree (Ficus benjamina) indoors or outside in your garden, you know it's an attractive tree with branches that droop gracefully. Also called the weeping fig, this plant is usually quite tolerant of most growing conditions. But occasionally the tree will drop some leaves, a possible cause for concern. Although this might not be serious, it could indicate the tree has a problem and needs some extra attention.

If your ficus tree begins to lose leaves, it suggests the plant is under some type of stress. It's common for incorrect watering to cause this problem -- the tree needs an even amount of water during its growing season, from early spring through summer's end. If leaves turn bright yellow before they fall, the problem is probably too little water, with overly dry roots stressing the plant. Correct this problem by watering the tree fully whenever the top 1 or 2 inches of soil feel dry to the touch, ensuring that water drips from the pot's drain holes if it's potted. If a container-grown tree's soil dries out every few days, repot into a larger container with more soil -- this helps soil stay moist for longer.

If young leaves or new leaves at branch ends fall while they're green, this may signal an overwatering problem. Don't water a tree when its soil feels moist at the surface -- wait until it's slightly dry. Never let a container-grown tree sit in a water-filled saucer and reduce watering in fall and winter, when the tree slows its growth and needs a rest. If overwatering is the cause of the tree's leaf drop, it may continue to lose leaves for several weeks once you correct the problem, but eventually new leaves should appear at stem tips to fill in bare areas.

A ficus tree could begin dropping leaves if a change in its environment stresses the plant. The ficus tree grows outdoors year-round in U.S. Department of Agriculture plant hardiness zones 10 through 12, but can over-winter indoors in colder regions. If you've moved a potted tree indoors, the change in air temperature or humidity might cause the tree to lose leaves, or this could be a response to a change from bright outdoor light to dimmer indoor conditions. The tree should recover eventually, but increasing the humidity by misting the plant every few days can also help. Over-winter the tree in bright, indirect light, such as near a curtained south- or west-facing window, but protect it from cold drafts, because this might also cause loss of some leaves.

A ficus tree usually has no serious pest or disease problems, but it can be susceptible to bacterial leaf spot, which causes yellow spots on leaves that eventually turn completely brown and drop off the tree. There's no effective treatment for this problem, but you can avoid it by only buying a tree that's certified free of the disease from a reputable supplier. A ficus tree might also attract spider mites, especially if grown in dry indoor air. These microscopic pests form webs that cover young leaves and, if left untreated, can cause leaves to drop from the tree. Destroy mites by spraying the tree with insecticidal soap diluted at a rate of 5 tablespoons per 1 gallon of water, or according to the label's instructions. Spray the tree until it's dripping wet and repeat every week or two, as needed.