I have several camellias, and they flower beautifully every year. However, the leaves are covered by a black soot, which I believe is caused by insects. Every year I clean it off as best I can with a strong blast from the garden hose, but the infestation always comes back. What are the conditions that encourage this type of infestation and what can I do to prevent it? Most annoying as the black stuff is usually worse at time of flowering, and I have to wait until after flowering to blast it off - don't want to ruin the buds. Pictures of a plant with a bad case of it:
No, it's specific only to camellias - does not appear on any other plants in my garden, even those in close proximity. And re-occurs every year. It is a sooty stuff that has to be rubbed off, or washed off with a very strong spray. I read that there's an insect that produces a sticky substance, rather like aphids. I plant my camellias under the eaves, to keep the flowers out of the rain, but I wonder if the drier conditions enable these bugs to prosper? Doesn't seem to have overly adverse effect on plants but is quite unsightlly.
Gee, good to hear it doesn't hurt the plant, hope somebody has the answer. Off topic , but beautiful tree peony pic submitted for photo of the day. You grow them very well, especially for this climate it seems. A little info here which you're likely familiar with www.efa-dip.org/en/Secciones/Verde_urbano/enfermedades/Meliola_cemelliae/index.HTM
Thanks. The tree grows itself without much help from me, other than my futile attempts to stake it perfectly. It's about 5 1/2 ft tall now so I'll soon need a ladder to take pictures of the flowers.
No seriously. Nada. No fertilizer, mediocre soil, and in a bed that gets quite dry in summer. This spring, I put some compost on it - hope I didn't disturb its happy place! From seed? Interesting. How many years for them to bloom? Sounds like you are more patient than I am. If you like, would be glad to send you some seeds to try out. I've got more than 50 flower heads this year so there's lots to go around. Btw, the little sprout that I found near the plant last year? I potted it elsewhere where it grew more this spring, and leaves are quite different, so must be something from the graft.
Hmm. maybe dryer would help here and some compost , thank you. About 7-8 years from seed to bloom, they weren't pushed with fertilizer. Thank you very much for the kind seed offer , it's tempting, but I'll decline for now. A slow process , but nice when they bloom. Maybe the little sprout is a herbaceous peony, guess you can tell by the leaves, might be a nice one too. Can't think of any bloom that compares with the TPs when they're blooming, very distracting . 50 blooms ! very nice. With the camellia, wonder if there is too much humidity with the drainpipe there and possibly low air circulation, if that might contribute to the black sooty mold problem. Maybe creating a preferable environment to aphids or scale . Some references to "sooty mold" using the "SEARCH'' box in the top title bar, likely you've already been through them. Other members may have some better suggestions or experiences.
What you have on your camellia is sooty mold. It is a fungus that grows on plants that have either aphids or scale (on camellias it's usually scale). The fungus grows in the excretions of the insects. On camellias, you can control the scale by spraying a light summer oil right as the new growth is starting. And the sooty mold can be cleaned off by wiping with a damp cloth, either with water or with vinegar.
Yes: You must locate and identify the source of the honeydew the sooty mold is growing on, remove that. Then the sooty mold will go away. If the source is scale insects with these there is a particular time each year when they are in what is called a crawler stage. It is often recommended to apply controls at this time.
I picked off a leaf and sure enough there were a couple of scale insects near the stem on the underside of the leaf. I don't think the drain pipe causes any extra humidity. If anything, the conditions are on the dry side, even in winter. I have camellias situated in different parts of the garden, even one in a pot by the front door, and they all somehow get infested. What sort of oil spray? I've heard of Neem oil but I think it's not sold in Canada? Hard to spray too, since they are on the undersides of the leaves and some of the bushes are quite large and leafy. Thanks for any suggestions! I've had this problem for a few years.
Just plain horticultural oil, summer weight, crawlers are active when new growth appears so that is the time to spray.
