Recognizing Powdery Mildew

[digitS']

Okay.

I don't need to have it explained. Anyone with squash and cucumbers this late in the season must know what powdery mildew looks like.

I'm embarrassed to show you the mildew on the pumpkin vines.

Most of the vines are burned from frost but all of the white in the corners isn't frost damage. Just beyond the the punkins is a zucchini, one of the last to be set out in July.

Another few days and that young plant will be white, also. Old plants are toast and not just the ones caught in the early-September frost. Marigolds and sunflowers, too ... Some years, it's worse. Mild weather is predicted again - that just means more mild-ew!

Is there ANY resistance in any of these plants to mildew? Do you find that some varieties get through the season better than others?

Steve

 

[thistlebloom]

Look at those beautiful pumpkins!

I can't speak for the veg patch, but for ornamentals this seemed like a very PMy year. I kept it at bay from the usual suspects like lupines and monardas with the oil spray I like. And the dogwood tree at one property that is always loaded with it looked pretty good all season because for a change I was more proactive in spraying early.

I know dragging a hose out there in some of your gardens isn't an option, but I wonder if the sesame oil would work in a backpack sprayer?

 

[digitS']

Sesame?!

I have these nice marigolds and both years that they have been around, I can't seem to get enough Bayer systemic on them to keep the mildew at bay. They are okay and the sunflowers, too. I don't try to spray the foliage on the sunflowers with that stuff.

Years ago, I tried neem and it didn't help nearly enough! I would feel comfortable using it on the veggies but wasn't encouraged, way back when. Sesame?

Looking at the climbing rose, it can get a shot of the sulfur spray along with the peach tree in late winter. I can use the systemic on it later.

Yes, I wanted to have a good shot at the pumpkins with my cell phone then I still got some of those terrible looking vines in the picture ...

Steve

 

[thistlebloom]

Well, it's a commercial OMRI approved horticultural oil and sesame is the main ingredient. It's called Organocide and is widely available. I usually pick it up from the big orange box. The one drawback is the mess it makes on the outside of my hose end sprayer, it gets all gummy and then the dust sticks to it and so on.

I suppose if I was diligent to wash the outside of my sprayer off with soap after each use it would be fine. I am only an occasional equipment cleaner upper, so except for my backpack sprayers, I only clean once in the summer, and the big one at the end of the season.