The jade plant is a popular, easy-to-care-for houseplant with few pest problems. Most of the insects that can feed on jade plants cause little damage but some can be quite problematic. Checking your plants often and knowing the steps to take can prevent a minor infestation from becoming a fatal problem.
There are several types of mealy bugs that affect house plants like jade. Some tell tale signs of their presence are leaves that turn yellow, distorted flowers, defoliation and with severe infestations, plant death.
Tiny little creatures leaving small webs throughout the plant are called spider mites. Specks and dust on leaves are other signs that they have taken up residence. Leaves may take on a scorched appearance followed by leaf drop. As with mealy bugs, severe infestations can bring about plant death.
Most plants have one kind of aphid or another feed on them. Damage is usually minimal and corrective action is usually not needed. In cases where the populations are large however, leaves become curled, yellowed and distorted. The aphids leave behind a gooey substance called honeydew which becomes a medium for growing a fungus with a sooty black appearance. Some aphids can inject toxins into the plant while others can create galls.
Scale insects are immobile pests that suck fluids from leaves and stems. Symptoms are similar to those of aphids. They can also leave halo-like blemishes in leaves and twigs. The presence of scale insects can slow growth. Severe cases can case parts of the plant to turn brown and die. Young plants infested for several years may eventually die.
Water is the cure for 3 out of 4 of these insect problems. A thorough rinsing under a garden hose or kitchen sink sprayer generally removes all the bugs and the residues they leave behind. The tricky part is not to flood out the roots as jade plants dislike soggy roots for any period of time. It is best to rinse the plants early in the day and place the plant in a warm, sunny place so that it can dry quickly.
Sources: Clemson University: Jade Plant
Cornell University: Jade Plant