In smaller numbers, aphids are a minor nuisance that won't affect your plant's overall health. In larger numbers, aphids are destructive and can cause yellowed and disfigured leaves, stunt growth and in some cases, plant death.
1. Check the underside of leaves regularly to see if you have a problem. Spotting it before it gets out of hand helps. If the plant is heavily infested I usually pull it out.
2. With a solution of 2 tablespoons Dawn dish soap to a gallon of water, spray off the leaves, making sure both sides are coated well.
3. Hose off the soap solution. If it is left on the leaves it can cause damage and burning.
4. Check the underside of the leaves later or the next day. Sometimes a second or third treatment is necessary.