Not sure if this is Downey (Downy) or powdery mildew or something else but the Marketmore 76 cucumber (right side in photo) seems to be resistant. Any idea how to treat future plantings organically of the non-resistant varieties -- Amernian Cuke is pretty much dead after the last rain (left side). I planted both at the same time.
Summer and winter squash seem to have the same problem. Zuchinni Elite Hybrid (left) seems to be a bit more resistant than the patty pan (right). Are there any known resistant cultivars? This is the late planting which seems to be more susceptible than the early one!
Here is a list pf Powdery Mildew resistant squash. Can't ise advanced search on cucumbers, but some of the newer hybdids do have PM/DM resistance. PM is fairly easy to control with a high pH fungcide. Sodium or potassium bicarbonate is widely used even by commercial growers. Some home gardeners use milk and a copper based (copper sulphate) fungicide will also work. http://davesgarden.com/guides/pf/advanced.php?nn%5B89%5D=0&nn%5B1%5D=0&nn%5B2%5D=0&nn%5B55%5D=0&nn%5B90%5D=0&nn%5B91%5D=0&nn%5B92%5D=0&nn%5B93%5D=4&nn%5B53%5D=0&nn%5B9%5D=0&nn%5B23%5D=0&nn%5B10%5D=0&nn%5B12%5D=0&sname=Squash&Search.x=26&Search.y=15
This message was edited Sep 21, 2007 9:02 AM
We've had very good success with the milk& water mix. Foliar feeding with liquid kelp seems to act as a preventative as well.
Some commercial growers also use the milk&water spray for powdery mildew, especially in South America. Info on formal studies here:
http://www.agrar.de/agenda/bettiol.htm
Slide 3 of the ATTRA presentation at this link gives some other options.
http://www.attra.org/attra-pub/PDF/IPM/disease.pdf
FarmerDill, we've found potassium bicarbonate less likely to burn the plant compared to sodium bicarbonate. Have you noticed this?
I hava not had a problem with either of the bicarbs, but I don't use high concentrations.
OH man, I am having the same problem with my winter squash, the black fatsu spelled wrong, fitsu or what ever you call them, are loaded, and it's spreading to all the other squash, long island cheese, hubbard, it's horrid. I can't do enough to keep it off.
Next year, I'll have to do something different, g row a diff kind or something.
