I have an ongoing fight going with some woolly aphids. They're seriously damaging my gardenia bush. I have the insects mostly under control with an insecticidal soap, but the sooty leaves are unsightly and hindering growth. . . not to mention giving these bugs places to hide. How far back can I prune this gardenia without killing it? There's been new growth on the branches, but I am unsure as to how much of the damaged older growth can be cut.
Pruning Gardenia Bush With Woolly Aphids
Certified GKH Gardening Expert
You can cut back up to a 1/3 of the plant in a season. I would suggest trying neem oil on the plant. We have found it to be very effective on aphids and it will also work to combat the sooty mold. This article has more information on neem oil: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm