By Mary-Jane Pilgrim, Master Gardener
Seeing bugs outside is generally pretty tolerable as we know that many of them are pollinators, but seeing them inside our houses is a completely different story, right? Fortunately, it’s usually easy to manage most indoor pests with little more than some water, a cotton swab, and a soap solution. It all starts with a few preventative actions:
- Whenever you happily bring home a new treasure (or sometimes, victim!), make sure that you carefully inspect them. Many types of houseplant bugs piggyback their way into your house from friend’s homes or stores. Look on leaf undersides, along the stems, and even in the soil for signs of common pests (sticky substances, flying cloud when disturbed, little bumps, fine silky webbing).
- Put your new treasure in solitary confinement for a few weeks, like in a spare room. Even if you think a new plant is pest-free, it may have pest eggs or larvae that you can’t yet see. Watch it carefully and only put it in close contact with other plants after it’s been confirmed to be pest-free. If the pandemic has taught us anything, quarantining is right at the top of the list and it applies to plants as well as humans.
- Place a few yellow sticky cards in among your plants. Many pest insects are attracted to the color yellow, and they’ll quickly get trapped on the card. Check the card every few days for any insects. If you have some on the card, you probably have many more on the plant itself.
What if You Detect an Infestation?
The most common pests are aphids, fungus gnats, mealybugs, scale, spider mites and white flies. See this resource for bug-specific instructions.
For all infestations, the first thing to do is to move the affected plant away from all other plants. Quarantine!
Then, take the plant to the bathtub/shower and spray it with water. Many bugs are tiny and are easily washed off the plant. Be sure to rinse both upper and lower leaf surfaces. After the plant has fully dried, use a light-weight horticultural oil or insecticidal soap to smother the pests. Reapply the oil/soap every 10-14 days for two more applications for the best control.
If you detect small bumps, wipe the plants with a cotton ball soaked in rubbing alcohol and remove the bumps if possible.
If you detect pests in the soil, it’s often caused by overwatering. Reducing the amount of water, or watering your plants from the bottom instead of the top should take care of the problem. Spraying the soil lightly with insecticidal soap occasionally often helps as well.