Succulent jade plants are popular houseplants because they are easy to care for and rarely suffer from pests or diseases. A healthy jade plant has plump, green leaves with glossy surfaces. If your jade plant has white dots or spots on its leaves, this could be a sign of insect infestation or incorrect growing conditions. Investigate any potential problem straightaway before it has a chance to spread.

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Jade plants produce white salt dots on their stems.

Mealy Bugs

Mealy bugs are small, soft-bodied insects up to 1/4 inch long. They are covered with a layer of white dust or filaments that are mobile. Mealy bugs gather on new stems and on the undersides of jade plant roots. Treat mealy bugs by dabbing them with a paintbrush dipped in a 70 percent solution of rubbing alcohol. Deal with severe infestations by using a systemic insecticide formulated for houseplants.

Salt

Jade plants naturally develop small crystals of salt on their leaves. The salt is absorbed through the roots and excreted by the leaves. It dries into small, white dots. You can't prevent these but you can remove them with a damp cloth. Flush out the soil of your jade plant with plenty of water if it is covered with a white crust of salt.

Oedema

Jade plants that receive too much water suffer from a condition known as oedema. The first symptom is develop blisters on the leaves. These pop and form small, corky spots that go from yellowish-white to brown. Reduce watering of jade plants showing signs of oedema. The spots that are already present are permanent but no new ones will appear. Oedema is most common on jade plants during the winter.

Other Causes

Water drops drying on jade plant leaves leave white spots on their surfaces, especially in hard-water areas. Wipe them off with a damp cloth. Jade plants exposed to household chemical sprays or hot cooking oil may also develop discolored spots on the leaves. Indoor jade plants kept in a humid room such as a bathroom sometimes develop powdery mildew on their leaves in the winter. Decrease the local humidity levels or increase the airflow around the plant to prevent it from growing again.