Pests. The common enemy of all plant parents. Facing an infestation can be extremely frustrating as it can spread quickly if not dealt with. While many houseplants’ parents may think that their plants are less susceptible to pests since they are indoors, pests are actually more likely to take residence on houseplants as they do not have natural predators to control them!

Catching the signs of pest infestation early is the best way to save your plants. Here is a handy guide on identifying the 6 most common houseplant pests and how to get rid of them!

Scale & Mealybugs

Identifying Scale

Scales are soft-bodied insects that appear as small bumps on plants. They come in a variety of different shapes and colours (Usually yellowish brown/ grey) and are often found on the stems and underside of leaves. Scale causes damage by sucking the sap of the plant, leaving it stripped of essential nutrients. 

Identifying Mealybugs

Mealybugs are actually a type of scale insect. They usually appear white in colour and colonies clustering together resembles blobs of sticky cotton wool. Similar to scale, they cause damage to plants by feeding on plant sap. 

Symptoms
Yellowing leaves, sticky honeydew, sooty mould, stunted plant growth

Other than the above symptoms, an ant infestation may also indicate the presence of scale insects. Ants farm these pests as they get to harvest the honeydew that scales produce for food! As scale insects can’t move, ants will carry them and move them from plant to plant.

Treatment
There is no easy cure for a scale infestation and multiple rounds of treatment may be needed before you can fully eliminate these pests. Spray your plant with neem oil or dab each scale insect with rubbing alcohol. You can also use your fingernail to scrape them off. Cut off any plant part that is severely infected. If your entire plant is heavily infected, toss the plant away to prevent spreading the infestation to other plants.

Spider Mites

Identifying Spider Mites

Spider mites are tiny reddish-brown, spider-like creatures that feed on the sap of leaves using their piercing-sucking mouthparts. They thrive in hot and dry conditions, and can often be found residing on the underside of leaves. Although spider mites often leave a tell-tale webbing on their host plant, many people mistake this webbing for normal spider webs, letting the infestations go unnoticed!

Symptoms
Sticking webbing on plant, mottled leaves with white/yellow spots, yellowing leaves, discoloration of leaves

Treatment
Spider mites infestation are notoriously tough to control (They are the bane of my existence

Aphids

Identifying Aphids 

Aphids are small pear-shaped insects that usually appear green in colour. They feed in groups and prefer new growth and the underside of leaves. Similar to scale insects, they suck on plant sap and produce sticky honeydew. As their life cycle is short, tey populate and spread rapidly. 

Symptoms
Yellowing flowers and leaves, sticky honeydew residue, white husks (their molt), stunted new growth, sooty mould

Treatment
Fight Aphids by wiping your plant down with rubbing alcohol or bringing your plant into the shower for a good spray down. Pick any remaining Aphids off the plant and crush them with your fingers. You can also treat an infected plant with soapy water or neem oil. Aphids are persistent and you may need to repeat the treatment multiple times before eliminating them.

Thrips

Identifying Thrips

Thrips are small, slender bugs that can do a lot of plant damage. They usually feed in groups, sucking sap from leaves, stems, flowers, and even fruits! Other than weakening the plant and distorting growth, they can also spread plant diseases!

Symptoms
Discoloration of leaves, Streaking/ yellowing spots on leaves, distorted plant growth, dropping of leaves, dying flower buds, black varnish-like specks (their excrement)

Treatment
Spray/ rinse your infected plant thoroughly in the shower to knock off the larvae and eggs. Apply systemic insecticide or neem oil after. You can also consider using yellow sticky traps to capture the adult Thrips!

Fungus Gnats

Identifying Fungus Gnats


Fungus gnats are more of a nuisance than a pest and they are not considered too problematic for your houseplants. Adult gnats appear as small black flies hovering over the soil surface. They are often the result of overwatering, where they breed in the damp soil of your plant. While adult gnats do not pose much of a problem for your plants, their larvae can cause damage as they feed on plants' roots.

Symptoms
Hovering small flies around plants, distorted plant growth

Treatment
Avoid overwatering and allow your plants' medium to dry out in between watering sessions. You can also use yellow sticky traps to capture the adult gnats to prevent them from breeding. Another common treatment method against gnats is mosquito bits. Soak mosquito bits with water and use this mixture to water your plants. Mosquito bits help to eliminate gnats larvae as they contain a bacterium that is poisonous to them when eaten.