Powdery Mildew on Euphorbiaceae
I’m having an awful time with mildew (or some similar fuzzy gray fungus) on Euphorbias in my house, one room in particular.[1] I tried neem oil, but that just makes everything defoliate. Then I tried spraying with basic copper sulfate (it was the cheapest and least toxic thing I could find at the garden center), but that has no effect. So I’m looking for something not found in nature, ideally something that’s illegal in multiple countries. Bonus points if it’s a yellow-green liquid that produces its own dry ice fog. Can you recommend anything?
Pedilanthus tithymaloides w/fungus
Euphorbia drupifera w/fungus
-
[1] Affected so far: Euphorbia milii, Euphorbia drupifera, Pedilanthus tithymaloides, Synadenium grantii, Euphorbia bougheyi variegata, Euphorbia trigona, Euphorbia lactea, Pedilanthus ‘Jurassic Park 2.’
You can also bookmark this on del.icio.us or check the cosmos
RSS feed for comments on this post. | TrackBack URI
December 13th, 2012 at 12:16 pm
Here are some other low impact ideas in a well-researched article by a master gardener friend.
http://www.mastergardeners.org/publications/powderyMildew.html
Cheers,
Bracey
December 13th, 2012 at 2:37 pm
Hadn’t considered baking soda previously (thanks, Bracey!); I remember we had a mildew problem on something at work, and that one of the people there suggested baking soda. (I don’t remember whether or not it actually worked. But I remember we tried it.)
Peroxide is also a possibility I wouldn’t have thought of: it helps that we already have some on hand.
I bought a bottle of chlorothalonil at the ex-job on Wednesday. It isn’t green, and it doesn’t fume, but it looks incredibly nasty all the same. (If I had seen a diagram of the chemical structure before I bought it, I would have gone with something else.)
I don’t want to spray that in the house, though, so I think what I’ll do is: I’ll start with peroxide. If that doesn’t work, then baking soda. If that doesn’t work either, then I’ll wait for the first unseasonably warm day we get (above 60F/16C) and try the chlorothalonil outside. With any luck, one of the other things will work first and I can just return the bottle. I mean, given the choice, I’d rather keep both my kidneys than keep the Pedilanthus/Euphorbia/etc.