Help identify this disease!

[Taylor O.]

My green beans (bush) were doing fine, then one day they started to turn whitish, yellow color. Now the leaves have dropped and it looks like the zucchini next to the beans is catching whatever got my beans. Help!!

 

[Beth_B]

That's powdery mildew and it will keep spreading unless you treat it.
Google powdery mildew + your state for more info.
There are many commercially available sprays, and many home made recipes (many involving mixtures of milk and dish soap), but I don't know which works best as it's not an issue I've dealt with much.

 

[Taylor O.]

Ok, great. Thank you Beth_B. I suspected it was some type of mildew, and now I have confirmation. The plants were planted a little too close together...maybe not enough ventilation?

 

[Beth_B]

That could certainly contribute! Most fungus and mildews require low light and moist conditions to proliferate. You don't say where you live but a rainy summer can wreak havoc on a vegetable garden.

Proper watering practices and mulching can help a lot too. But sometimes Mother Nature has her own agenda. Try searching "powdery mildew" on this forum or via search engine and you'll get lots of feedback.

 

[headfullofbees]

The probability of the occurrence of powdery mildew is hugely increased when the leaves are damp, but the roots are dry.
Mix 1 part milk to 4 parts water and spray all leaves both sides; it doesn't like the alkaline environment and the spores can't open.
Won't save damaged leaves, (nothing will), but will protect new and undamaged leaves.

I'm not certain, however, that it is powdery mildew, or only powdery mildew; I believe you may also have a problem with magnesium deficiency.
Add one good handful of horticultural Epsom salts per watering can, and give the ground around these plants a good soaking with this.

 

[Corzhens]

Oh, oh, I don't know how that is called but definitely it is some kind of parasite. As usual, my suggestion is to spray the affected leaves with a mixture of water and liquid dish washing soap. Leave for 5 minutes after the spraying before rinsing with water (using garden hose is better).But do the spraying during noon when the sun is hot so the water on the leaves will easily dry. Never spray at night for the parasite love to multiply on wet surfaces. .

 

[Taylor O.]

The probability of the occurrence of powdery mildew is hugely increased when the leaves are damp, but the roots are dry.
Mix 1 part milk to 4 parts water and spray all leaves both sides; it doesn't like the alkaline environment and the spores can't open.
Won't save damaged leaves, (nothing will), but will protect new and undamaged leaves.

I'm not certain, however, that it is powdery mildew, or only powdery mildew; I believe you may also have a problem with magnesium deficiency.
Add one good handful of horticultural Epsom salts per watering can, and give the ground around these plants a good soaking with this.

I bought an "organic" spray to help prevent the powdery mildew. I couldn't find much regarding getting rid of it, but only info on prevention.

If it's not a mildew, would the magnesium deficiency have a tendency of spreading? I'll do my research... I'm a new gardener. It's all about trial and error for me right now.