|My gardenia bush has been struggling with those small, starts off green on the underside of fresh leaves,scale type bugs for most of it's 6 years of free range growth. It's about three 1/2 feet round. I have noticed that the branches will also get covered with a blackish sooty covering when the infestation gets large. Insecticidal soap only seems to hurt more than help so I have taken to spending too much water and lots of time blasting the bugs off. I also noticed the black sooty cover on the branches can also be blasted off revealing green stems beneath which then seems to fortify it to grow faster. Unfortunately I have do do this just about every month, is there any other way to control these problems? Also I worry about where these|
|What you describe are scale insects. The adults attach themselves to a stem and feed on the fluids within the tissues of your gardenia. They exude a sticky substance called honeydew. This substance has a high enough sugar content to turn a moldy black - it is commonly called sooty mold. It can be wiped off the leaves or will weather off on its own. To eliminate the sooty mold and the honeydew, you need to eliminate the scale insects. After attaching themselves to a plant stem, the female scales give birth. The baby scales are able to crawl up or down a stem until they find a likely feeding spot. If you can catch the little scales in this crawler stage, you can eliminate them, plus any future populations so continuous spraying will be necessary until you kill off the entire population. It will be worth the effort - just keep at it!
As for hosing the pests off the plant, they usually die. If they land on grass or concrete or gravel or bark, they won't be able to attach themselves to feed and will perish in a short time. So, don't worry about them crawling back up on your plant.
Hope this answers all your questions.