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Powdery mildew

17 years ago

Hello! I bought six hydrangias last spring (the mophead kind) and they made it fine through our hot summer in pots on my covered porch. For the last month or so, the leaves on a few of them have been covered in powdery mildew and falling off. The stem seems fine and there are green leaf buds at the point where the leaves were. I am an organic gardener, so sprays are not an option. My question realy is, should I be concerned? I also want to know if hydrangias grown in Florida usually loose their leaves in the fall like deciduous plants, or should they be more evergreen? Does this depend on the variety? Is there anything besides chemicals that I can use to control the p.m.? I am an old pro at roses, but hydrangias are a mystery to me! Thanks!

florie

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Comments (4)

yellowgirl
17 years ago
Sounds par for the course. Even with the sprays, PM is almost inevitable with such high humidity we have down here. Don't worry, in Spring, fresh new untainted leaves will sprout again. They are still tardily deciduous here in Orlando and depending on conditions, mostly sun exposure, some will fall earlier than others, but they will all eventually fall. Potted hydrangeas may behave just a little differently because they can be moved to ideal or sheltered locations with ease. I've seen the potted hydrangeas of others keep their leaves year round, but the leaves that remained were very diseased and in need of manual removal anyway. Don't forget to keep watering the dormant ones, albeit less often, over the winter months. Hope this helps.....yg
Florie
Original Author
17 years ago
Thanks yellowgirl. I am glad to hear that it's normal stuff. I am tempted to plant them in the ground on a north wall. In the summer, the area gets a bit of sun in the morning and shade in the afternoon, but in the winter, it is in all shade. There is a house nextdoor that reflects light onto the wall. Does this sound like a possible site for permanent planting? The soil at my house is more of a moist landfill type- it is not the typical sand. I would defeinitely amend it to improve drainage. I have heard that the tricky thing to hydrangias is that they don't like it too moist or too dry. My roses flurish in the stuff because it never is bone dry. Sometimes in the summer when it rains a lot, the soil is mostly wet, almost mucky.
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yellowgirl
17 years ago
The light conditions sound good. North or east sides are not only best, but they are the only sides that are not too hot for hydrangeas down here without a substantial amount of tree shade. However, the "mucky" part is not good. They will need an abundance of water in the ground here but good drainage is always a requirement. Oh yeah, and patience too!! ...yg
Florie
Original Author
17 years ago
Ok, I think I will give it a shot with three of the six I have in pots. I will amend the soil with some really loose stuff to try and improve the drainage.

Last year, I drove by an old lake home here in Tampa, and the entire north side of the house was all bushes of beautiful blue hydrangeas. The property looked neglected, but when I saw these, I had hope that maybe I might have the same beautiful blooms one day. I'll keep you posted!

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