TL;DR: Aphids are small green insects that feed on plant sap. Wash them off with soapy water, spray them off with water, or apply neem oil. Act quickly as they multiply fast.
What aphids look like
Aphids are a few millimetres long with a rounded body and small antennae. They are usually green, though other colours exist. You will typically find them clustered on soft stems or the undersides of leaves. Signs of an infestation include misshapen or discoloured leaves and, in heavier cases, a sticky residue on or around the plant.
How to get rid of them
- Soapy water: Prepare a tub of mild soapy water and submerge the affected parts of the plant. The aphids will fall off. Rinse with clean water afterwards.
- Spray bottle: A strong jet of water will dislodge aphids from leaves and stems. Repeat daily until they are gone.
- Neem oil: An effective repellent for indoor use. Apply to the affected areas. Avoid using neem oil on plants you are growing to eat.
- Physical removal: For small infestations, wiping the aphids off by hand or with a damp cloth is often enough.
How to avoid them in the first place
Aphids are unlikely to appear in a Gathera system kept away from open windows and doors. The main risk is cross-contamination from outdoor soil or other houseplants. Keep your growing space clean and inspect new plants before placing them near your garden.