Cucumbers....powdery mildew? Please help (ADDED PICS!!!!)

SLC · Wed Jul 25, 2012 3:12 am

I am not sure if this is the problem, but from the research I have done, it sounds kind of like it. I do not have a picture, but I can take one tonight if needed.

I have two cucumber plants growing on a trellis. It has been doing just fine, and then yesterday I go to check out my plants and almost all of the leaves on this cucumber plant are getting yellowing spots, and then I turned one of the leaves over and there was this white powdery stuff (which is why it might be this powdery mildew disease). The cucumbers growing seem fine so far - lots growing.

What should I do? I do have this organic plant spray for fungus (I think that's what it says anyway). Should I use that for this? Do I spray just the leaves? Top and bottom? Or do I spray the stems? What about the growing cucumbers?

SLC · Sat Jul 28, 2012 3:33 am

Okay, I finally took some pics:

The whole area - just 2 plants, but if you zoom in, you can see all the leaves are turning!!!

[img]https://img.photobucket.com/albums/1003/SecretlyLovesClay/Garden/P1090281.jpg[/img]

Closeup of the leaves:

[img]https://img.photobucket.com/albums/1003/SecretlyLovesClay/Garden/P1090284.jpg[/img]

[img]https://img.photobucket.com/albums/1003/SecretlyLovesClay/Garden/P1090283.jpg[/img]

Under this leaf, it looks like this:

[img]https://img.photobucket.com/albums/1003/SecretlyLovesClay/Garden/P1090285.jpg[/img]

I checked every other leaf and none others have this - they all look fine (so far):

[img]https://img.photobucket.com/albums/1003/SecretlyLovesClay/Garden/P1090286.jpg[/img]

Any suggestions??? I've only gotten maybe a couple dozen cucumbers so far...is the plant done or should I get more out of it? There are a few more growing...

gixxerific · Sat Jul 28, 2012 6:24 am

Yes just spray the leaves and stems with fungacide. Preferably organic there are many things you can use. You need to try and get all surfaces, though I find this impossible so get as much as you can.

Also DO NOT compost the plant when you are done with it.

Good luck it doesn't seem that bad yet if you attack it quick you may save them.

gixxerific · Sat Jul 28, 2012 6:26 am

Oh yeah cut off the worst offenders and than spray. Discard these in the trash or burn them.

SLC · Sun Jul 29, 2012 9:56 am

Thank you again for the advice! I wouldn't have known not to put it in the compost pile...my bf says to just throw everything in there... But the thing is, that will be what is going in my garden next year! And I do have organic spray, I bought it just I case - good thing I did. I want it to bean organic garden...I even told him he wasn't allowed to put the grass clippings from the front yard in there since he uses weed killer and fertilizer on there.

applestar · Sun Jul 29, 2012 10:48 am

My favorite preventive and turn them around in early stages anti-fungal spray is milk spray -- Iused to call it 10% Milk Spray solution but it's become increasingly evident that somewhat higher concentation is more helpful. But I'll spray with whatever I got in a pinch. I usually add some strained "whey" liquid from yogurt.

1 part milk of any fat content, cow or goat, and 9 parts water to start with as a preventive before you notice any symptoms as soon as hot and humid weather hits. Some people say up to 50/50 is OK though I'm too cheap to ever spray at that concentration. I sometimes just use the ortho hose end tree and shrub sprayer.

I just love that I can spray it everywhere and even turn my face up to the falling mist for a quick facial.

gixxerific · Sun Jul 29, 2012 11:00 am

Apple you put milk in the hose end sprayer? Cool idea I do the same with fish emulsions etc. sometimes in line with a sprinkler.

applestar · Sun Jul 29, 2012 11:07 am

Fish emulsion is NOT as pleasant to spray....

gixxerific · Sun Jul 29, 2012 11:18 am

applestar wrote:Fish emulsion is NOT as pleasant to spray....

LOL not good for a facial.

sheeshshe · Sun Jul 29, 2012 11:41 am

gixxerific wrote:
applestar wrote:Fish emulsion is NOT as pleasant to spray....
LOL not good for a facial.

My thoughts exactly

PunkRotten · Mon Jul 30, 2012 3:08 pm

So this milk/water spray is only good as a preventive? I am pretty sure my melons and cukes got powdery mildew and some leaves are looking really bad. I need to do something soon. I got maturing melons and I am afraid the plant may die before I get to pick them.

applestar · Mon Jul 30, 2012 3:56 pm

It's best used as preventive but I believe in stronger concentration, it can slow down infections and some resistant varieties can recover with persistent care to reduce other stresses and some cooperation from Mather Nature.

There are studies about what it works best for and what not.

In case of severe infection, I actually like to alternate foliar milk spray with AACT spray.

PunkRotten · Mon Jul 30, 2012 4:36 pm

What is AACT spray?

rainbowgardener · Mon Jul 30, 2012 11:39 pm

Aerated Activate Compost Tea. Compost in water brewed with a bubbler to keep the mixture aerobic. There's a huge Sticky thread about it at top of compost section:

https://www.helpfulgardener.com/forum/viewtopic.php?t=17097

Other remedies for powdery mildew are baking soda solution or 3% hydrogen peroxide, straight from the bottle.

PunkRotten · Fri Aug 03, 2012 2:49 pm

I applied Peroxide and I think it helped a little. Maybe slowed it down but still is present. I am making Compost tea now. Got a 5 gallon bucket, added a big shovel full of compost and 2 cups of white sugar. And I have an air pump bubbling in it too. After about 2-3 days I am gonna use it.

applestar · Fri Aug 03, 2012 8:29 pm

I try to use AACT at about 36 hrs. After that the tea is supposed to get more bacterial rather than fungal and the way I understand it, 36 hrs is about when they are nicely balanced.