Pests?! Not in My House! Houseplants & Beneficials

We’ve heard it said that pets are the new kids and plants are the new pets. If that’s the case, then it’s no wonder houseplant enthusiasts want only the best for their leafy roommates! It can be devastating to come home and find that beautiful Philodendron or Prayer Plant suffering from an infestation.

In this post from A Bug’s Blog, we’ll cover some common houseplant pests and the Beneficial Insects that can help you combat them.

Bad Bug: Mealybugs

Mealybugs, often called "woolly aphids," are soft scales covered in a fuzzy, waxy secretion that serves as protection and reduces the effectiveness of contact pesticides. They harm plants by consuming sap and covering them in cottony white clusters. Mealybugs often cluster near the soil or on new growth, causing stunted growth and stress to plants.

Bad Bug: Aphids

Aphids are small, fast-reproducing insects that cause damage by sucking sap from plants. They are typically green but can vary in color depending on species. Some aphids have wings, while others do not.

Good Bugs:

• Ladybugs
• Green Lacewings
• Aphidius ervi, Aphidius colemani, Aphelinus abdominalis, Aphidoletes aphidimyza

Fun Fact: Parasitic wasps like Aphidius and Aphelinus lay their eggs inside aphids, which their larvae then consume from the inside out—nature’s most brutal pest control!

Pro Tip: Hang Yellow Sticky Monitoring Traps to detect and control infestations early.

Ladybug feasting on aphids.

Bad Bug: Thrips

Thrips are tiny pests that scrape and suck juices from fruits, flowers, and leaves. Damaged plants appear pale, silvery, and scarred, with leaves that may twist and die.

Good Bugs:

• Amblyseius cucumeris
• Hypoaspis miles
• Ladybugs
• Lacewing Larvae
• Amblyseius swirskii

Predatory mites like Amblyseius cucumeris and Amblyseius swirskii are excellent at targeting thrips larvae and eggs. 

Pro Tip: Sticky Thrips Leafminer Traps are a great addition to your pest management toolkit.

Bad Bug: Spider Mites

The two-spotted spider mite is the most common species of spider mite. These pests feed on the underside of leaves, causing stippling damage and forming tight webs along stems. They thrive in hot, dry conditions.

Good Bugs:

• Phytoseiulus persimilis
• Neoseiulus californicus
• Neoseiulus fallacis
• Amblyseius cucumeris

Pro Tip: Phytoseiulus persimilis specializes in two-spotted spider mites, making it a top choice for targeted pest control.

Bad Bug: Whiteflies

Whiteflies are small, winged pests that often appear in hot, humid conditions. They feed on the undersides of leaves, causing yellowing, leaf drop, and weakened plants.

Good Bugs:

• Encarsia formosa
• Delphastus catalinae
• Eretmocerus eremicus

Pro Tip: Catch whitefly infestations early by combining predators like Encarsia formosa with Yellow Sticky Monitoring Traps.

Bad Bug: Fungus Gnats

Adult fungus gnats thrive in moist warm soils and grow mediums, they do not damage plants, but are seen as a nuisance in greenhouses and indoor grows. However, the fungus gnat larvae, which reside in the soil, damage roots and stunt growth, particularly in seedlings and young plants. A wilting, droopy plant may not indicate a lack of water, but rather root damage by fungus gnats. They are usually found in wet, over-watered soils or grow mediums.

Good Bugs:

• Stenernema feltiae Nematodes
• Hypoasmis miles
• Dalotia coriaria

Nematodes such as Stenernema feltiae and predatory mite Hypoaspis miles are both predators that attack the fungus gnat larvae in the soil. For high infestations, Stenernema feltiae, Hypoaspis miles, and  Dalotia coriaria (rove beetle) will co-exist and may all be released together.

Pro Tips:

• Remember, when it comes to using Beneficials, you always want to think preventatively. Be proactive and put them to work before you have a bad infestation.
• Sachets (seen in the photo above) are an easy, convenient way to apply beneficial insects indoors and out!
• If you are worried about releasing larger Beneficials like ladybugs or green lacewings indoors, try using insect netting over your plant. This netting can be found at most nurseries/growers supply stores, traditionally used for keeping insects out, in this case, it can be used to keep the good bugs in.
• With most Beneficials, we recommend releasing multiple times during the growing season.