Spider plants are popular houseplants, but owners sometimes notice small, brown bumps. This article clarifies what these common bumps are and offers practical solutions for addressing them.
Identifying Brown Bumps
Those small, brown bumps on your spider plant are most commonly scale insects, which are sap-sucking pests. These insects often appear as tiny, oval, or rounded growths that are slightly raised and have a hard, waxy, or shell-like coating. They can be beige, tan, or brown, and vary in size, with larger ones reaching about an eighth of an inch long. Sometimes, these bumps might be mistaken for natural nodes or part of the plant’s structure due to their appearance.
Scale insects attach firmly to the plant, making them difficult to identify as insects. You will find them on stems, along leaf veins, and on the undersides of leaves. A significant sign of a scale infestation, especially with soft scale species, is the presence of a sticky, clear substance called “honeydew” on the leaves or surfaces below the plant. This honeydew can also lead to the growth of a black, sooty mold.
Treating Brown Bumps
Upon identifying scale insects, isolate the affected spider plant immediately to prevent spread. For minor infestations, manually remove visible scales using a fingernail, soft brush, or a cotton swab dipped in rubbing alcohol. Rubbing alcohol helps break down their waxy coating, making removal easier.
After manual removal, apply a diluted solution to the entire plant. Options include rubbing alcohol (one cup of 70% alcohol with a few drops of mild dish soap and water) or insecticidal soap, which suffocates insects on contact. Neem oil is another organic option, typically mixed at one to two tablespoons per gallon of water with a small amount of dish soap as an emulsifier. Spray all plant surfaces, including undersides of leaves, ensuring thorough coverage. Repeat treatments every few days or weekly are necessary to catch newly hatched scale nymphs, as initial applications may not affect eggs.
Preventing Brown Bumps
Maintaining optimal environmental conditions for your spider plant helps reduce its susceptibility to pests like scale. Spider plants thrive in bright, indirect light, as direct sunlight can scorch their leaves. Consistent watering is also important; allow the topsoil to dry slightly between waterings to prevent both overwatering and underwatering, which can stress the plant. Spider plants also appreciate moderate to high humidity, so addressing dry indoor air, especially during winter, can contribute to their overall health.
Regular inspection of your spider plant is a simple yet effective preventative measure. During routine watering or grooming, examine stems, leaf joints, and both sides of leaves for unusual bumps or stickiness. Early detection allows for prompt action before an infestation becomes severe. When acquiring new plants, quarantine them for three to four weeks in a separate area. This isolation period allows observation for hidden pests or diseases, preventing spread.