Houseplants are vulnerable to attacks from various mite pests and insects. Bugs on houseplants are not only a nuisance, but are also capable of causing extensive damage to the health and appearance of the plant.
Stressed houseplants or those that are not vigorously growing are liable to be infected by mites. Oft, houseplant bugs that infest plants come from recently purchased plants or plants received as gifts. This is why all new plants should be kept in an isolated area for at least a period of three weeks. The isolation period gives one ample time to determine the presence or absence of bugs on houseplants.
Common Houseplant Bugs
There are various houseplant bugs infesting plants. Some of the common ones are as given below.
Twospotted Spider Mites
Twospotted spider mites are one of the most common pests infesting houseplants. These pests crawl from one plant to another, thereby infesting all plants in the nursery. They feed on plant sap and produce small wounds that appear like white flecks on the outer plant cells. The onset of the infestation more or less looks like small patches on the underside of the leaves, at the base of the leaf veins. Gradually, as the infestation increases, the leaves develop a grayish-bronze appearance. Oft, they even make webbing, which in very high populations is clearly visible.
Leaves that are heavily infested drop prematurely. It is difficult to control spider mite infestation. It is advisable to discard all the plants infested, since these will serve as breeding grounds for new infestations. Poor environment aggravates spider mite growth, thus, it is important to maintain optimal growing conditions to keep them at bay. One way to control their spread is by repeatedly washing the small plants with a jet of water. This will force the eggs and the nymphs to get washed off, thereby reducing the mite population levels.
This common pest is found infesting greenhouse-grown vegetables such as cucumbers, tomatoes, etc. It is also observed to infest plants such as lantana, hibiscus, etc. Greenhouse whiteflies are most commonly seen in the winged adult stage, wherein they are more or less gnat-like, covered with fine white wax. These pests suck sap from the plant, thereby causing damage to the plant. Heavily infested plants are observed to have reduced vigor. Moreover, during feeding, the sticky honeydew excreted by these whiteflies detracts the appearance of the plant. To curb the infestation, one can resort to using tape or yellow sticky cards so as to trap adult whiteflies. Moreover, vacuuming can be carried out on small plants to eliminate the whiteflies. Neem insecticides, horticultural oils, and insecticidal soaps can be used to destroy nymphs on the leaves.
These soft-bodied insects suck sap from the plants, thereby weakening it and causing its leaves to shed prematurely. Generally, jade, poinsettia, coleus, lantana, and cactus are seen to be commonly infested by these bugs. These pests affect various regions of the plant, from the root to the leaves. The infestation on the leaves is the most visible, however, these pests are mostly seen in the roots. To get rid of bugs on the leaves of your houseplant, you can swab individual mealybugs with alcohol or insecticidal soap to curb their population. Systemic insecticides like disulfoton and imidacloprid are also quite effective soil applicants.
These pests are tiny, dark-colored flies flying across the soil surface. They collect around windows and create loads of nuisance; however, they do cause little or no damage to the houseplants. These flying bugs develop in potting soil, thus, there is no particular plant that this pest infests. Common in garden and lawn soil, these pest populations can be restricted by changing soil moisture conditions. This is because fungus gnat larvae feed mostly on decaying plant material, therefore, changing soil moisture conditions will help. Moreover, watering should be limited, so as to permit the soil surface to dry between two consecutive watering. Yellow sticky cards can be used to capture the adult gnats.
Other Common Houseplant Pests
These sap-feeding pests when in large populations, cause plant wilting and new growth destruction. They can be best controlled by biological methods such as the predatory midge.
These tiny insects cause faint, irregular, silvery regions on the leaf's surface. They can be controlled by oils and soaps. Sticky tape is beneficial in attracting the adult thrips.
These pests infest twigs and leaves and are difficult to control, since their protective covering nullifies the effect of contact insecticides. Spray oils are the most effective to manage them.
These pests are round in shape with distinctive, central spots. They cause spotting around their feeding sites and can be controlled by horticultural oils. Systemic insecticides are not effective in controlling the infestation in this case.
These tiny gray or cream colored pests thrive on decaying organic matter present in the soil. These pest cause little damage to houseplants, however, they are annoying. Limiting water helps reduce their population numbers.
There are various ways to get rid of bugs on houseplants. Washing plants repeatedly with jets of water helps curb aphid and spider mite population. A handpicking technique can be used to control larger houseplant bugs like mealybugs, etc. Vacuuming helps get rid of whiteflies. Moreover, trapping some of these insects using yellow sticky cards is also useful. Natural enemies of these houseplant pests serve as great biological control methods. Besides alcohol, systemic insecticides, insecticidal soaps, horticultural oils, and seed extracts from neem plant are some other techniques of controlling these pests.