What it is
A tiny insect (1 to 2 mm), white, with wings, related to aphids. It lives under the leaves, sucks their sap and secretes a sticky honeydew. A black fungus (sooty mold) grows on that honeydew and covers the leaf.
How to tell
When you move the plant, a little cloud of tiny white flies takes off. Under the leaves there are tiny eggs and flat larvae. The leaves end up sticky, with yellow dots and, over time, black spots.
What favors it
Heat, still air and humidity. It comes in from other plants in the house or garden.
How to fight it
Potassium soap or neem under the leaves, repeating several times. Yellow sticky traps (they are attracted to that color) help catch the adults and show you if they are around. Moving the air with a fan bothers them.
How to prevent it
Don't let the air get too humid (over 60 %) or too hot, and check often with the lens.
▲ Pros
- Caught early it heals almost without damage
▼ Cons
- Untreated it can kill the plant, and in a batch it spreads to the next batches
🎮 Practice it in UnderGrow
Treat it with potassium soap (treat). It is favored by over 26 °C and humidity above 60 %. At first you only see it with the lens.
▶ Play free