Aphids are small insects, sometimes called plant lice, which normally feed on new or tender parts of plants both indoors and outside. Aphids are usually found in groups or colonies. The insects are oval shaped and roughly 1/8 inch in length. They occur in a wide variety of colors. There are several organic methods to control and eliminate aphids in the home.
Aphids in Houseplants
Aphids are rarely fatal to plants, according to the University of Missouri Extension service. They can reduce the growth rates of plants and cause discoloration or curling of leaves. Look for aphids on the underside of leaves and on new growth. Aphids have a needle-like mouth used to suck liquids from the plants.
Aphids sometimes excrete some of the plant sap they consume. This sticky substance is referred to as honeydew. An unsightly black mold can form in the honeydew which distracts from the appearance of the plant and can affect the plant's health by restricting the amount of light reaching the leaves.
Biological Control of Aphids
Several insects consume aphids. Ladybugs, sometimes called the ladybird beetle, are among the insects that eat the entire aphid. Other aphid predators include green lacewing larvae. Some nonstinging wasps, for example, lay eggs on the aphids. When the egg hatches, the wasp larvae consume the aphids.
Houseplant owners should be careful to not kill aphid predators when attempting to eliminate aphids.
Physical Control of Agents
Aphids can be washed off plants. According to the University of Missouri, stronger plants can be washed with a stream of water to remove aphids. Smaller plants that wouldn't tolerate a strong stream of water can be washed with a damp rag. Plants can also be dipped in water.
Infested leaves can be pruned from the plant. Seriously infested plants should be removed from the house.
Discourage Aphid Infestation
Aphids prefer the new tender growth of plants. Over fertilization can produce excessive plant growth including a large amount of growth attractive to aphids.
Make sure the plant is healthy. Adequate water and sunlight promotes a healthy plant that will tolerate small infestations of aphids without signs of stress.
Inspect any new plants for aphids before bringing them into the house. It is also advisable to keep the new plant isolated from the rest of the houseplants until it can be reinspected in a week or so after the first look. This ensures no aphids developed from eggs after the first inspection.