|I bought a beautiful staked gardenia last summer--the last time it bloomed.
Im having problems with yellowing leaves and
|Instead of the systemic, you can spray with insecticidal soap to get rid of the aphids, and this may wash off the sticky coating and the mold as well. If not, you may need to wipe each leaf with soapy water. Yellowing leaves can be caused by over or under watering or may just be a symptom of the aphid feeding. Gardenias often develop yellow leaves for no particular reason at all. Once you get the insect population under control, I think your plant will perk up. Water your plant deeply then allow the top half inch of soil to dry out before watering again. Feed with an acidified fertilizer (such as Miracid), get rid of those aphids and I think your plant will recover. Hope it's soon|