What are these big white fuzzy bugs on my plant leaves and how do I get rid of them?

What's likely going on

The white, fluffy mass on the leaves is not a fungus. It’s a group of insects that hide under waxy, cotton‑like fluff. From the photo, they’re most likely:

• Woolly aphids or
• Planthopper nymphs (sometimes called “fluffy bums”).

Both are small sap‑sucking insects that gather in big clusters and produce that striking white, hairy coating. From a single photo it’s hard to say exactly which species, but the treatment is the same.

They feed by sucking plant sap, which can cause curling leaves, slow growth, sticky honeydew, and black sooty mold later on.

What to do

1. Physically remove as many as possible
   Take the plant outside if you can and blast the clusters with a strong jet of water (from a hose or spray bottle on “jet”). This alone can remove most of them.

2. Wipe heavily infested leaves
   For reachable leaves, wipe the bugs off with a damp cloth or cotton dipped in soapy water (a few drops of mild liquid soap in a cup of water).

3. Spray with insecticidal soap or neem oil
   Use a ready‑made insecticidal soap or neem oil spray, coating the tops and undersides of leaves and stems. Avoid doing this in full hot sun to prevent leaf burn. Repeat every 5–7 days for 3–4 rounds.

4. Check nearby plants
   These insects move around easily. Inspect neighbouring plants and treat any new clusters early, before they build up.

5. Clean up honeydew
   If leaves are sticky or getting black mold, gently wash them with soapy water, then rinse.

How to prevent it

• Avoid over‑fertilizing with high‑nitrogen fertilizer; soft new growth attracts sap suckers.
• Keep plants spaced so air can move between them.
• Regularly inspect the undersides of leaves, especially in warm, humid weather.
• Encourage natural predators (ladybugs, lacewings) by avoiding broad‑spectrum chemical insecticides.

When to worry

• New leaves are coming out distorted, curling, or yellowing.
• You see thick, sticky honeydew and black sooty mold spreading.
• Despite several weeks of washing and spraying, the insects keep returning in huge numbers.

In those cases, step up control (more frequent sprays, or a systemic insecticide if local rules allow and there are no pets/children that might contact treated plants) or consider pruning and discarding the most heavily infested parts of the plant.