Jade plants (Crassula ovata) can be grown from a single leaf and end up over 5 feet tall. They have fleshy branches and rounded, glossy leaves. As succulents, they require little water but grow best in bright light with some direct sunshine. Jade plants lose older leaves naturally but an increase in the rate of leaf loss is often the first sign of a problem.

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Jade plant leaves drop when the plant is stressed.

Underwatering

Jade plants that are not receiving enough water often shed their older leaves. If the lower leaves on your plant are shriveling up and then falling off, check its soil. If it is completely dry, water your plant thoroughly. Water a jade plant every time the top inch of its soil is completely dry. Jade plants add leaves and shoots during the summer and need more water during the hot summer months.

Overwatering

Succulent jade plants are vulnerable to rot and must never be left with their pot standing in water. Check your plant's soil if its leaves turn yellow and start to drop off. Do not apply any more water until it has dried out completely. Remove the plant from its pot if you notice any soft sections on the trunk or branches. Wash all the soil off the roots and place it on a windowsill for a week. Cut off any branches or roots that are soft and repot in cactus potting mix.

Light

If your jade is losing its lower leaves at the beginning of winter this is likely to be because of low light. Move your plant closer to a window to increase light levels. Jade plants that are kept close to a window will shed leaves if they touch the glass on very hot or very cold days. Keep the plant a few inches back from the glass.

Temperature

Keep jade plants above 50 degrees Fahrenheit during the winter as cold temperatures will damage the leaves. Frost will kill your jade plant completely. Jade plants will shed leaves if they are placed in a cold draft or close to a radiator. A sudden change in temperature caused by a move will also cause leaf drop. The leaves will grow back once your plant has adapted to its new surroundings.

Leaf Shine

Never use leaf shine products on jade plants as it will cause all their leaves to turn yellow and fall off. Household chemicals and cleaners have a similar effect if they touch the leaves. Jade plant leaves shine naturally if they are dust free and the plant is healthy.

Pests

Jade plants are vulnerable to infestations of mealy bugs and scale insect. Mealies and scale make jade leaves sticky and can encourage the growth of molds. They also cause leaf drop and deformed leaves. Treat mealies and scale by dabbing them with a paintbrush dipped in a 70 percent solution of rubbing alcohol.