I think my gardenia has aphids. I was told that I should purchase a soap bath, specifically insecticidal soap, which I did. It seems that since I have been using it, it has gotten worse. The leaves also turn yellow and drop off. The stems are covered with a white, sticky substance. This plant has been in the house ever since I purchased it. Can you help me by telling me what to purchase to get rid of these pests?
Certified GKH Gardening Expert
I would recommend spraying the plant with neem oil. It is very effective against aphids. In addition, it is organic, being safe for other plants as well as harmless to pets and people. You can find more information here: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm