Powdery mildew on pumpkin leaves

[ChrisC_77]

I only have a slight concern, but seeing as how there is still a good bit of the growing season left, I want to address this. My sugar pumpkin has a few leaves with powdery mildew. I would say it's on 5 or 6 of the larger leaves on the lower part of the plant as I am trellising it. Plant and most leaves look healthy. Growing quite fast. Should I not bother it, or cut off those leaves or spray something on those leaves (organic or home remedy). The silver markings on all the leaves appear to be a characteristic of this variety.

[rainbowgardener]

Very common in squash family plants. Yes, you do want to do something about it or it will slow your plants down a lot and probably eventually kill them a bit early. Remove the most affected leaves and then spray all the rest, including the undersides of all the leaves. You can use a diluted milk solution (any where from 1 part milk to 9 parts water, to 50:50, let the milk stand out at room temperature for a little while to culture the bacteria) or a baking soda solution (1 tablespoon of baking soda, ½ teaspoon of liquid soap [NOT detergent, something like Dr Brunner's pure castile soap, 1 gallon of water) or 3% hydrogen peroxide straight from the bottle. Pick one, don't mix. But they will have to be renewed every week or two or after it rains, so you can alternate treatments, see which works best for you.

All of these work best preventatively, so be sure to spray all your squash family plants, whether or not they are showing signs of the mildew.

[ChrisC_77]

I will try the milk one first and see how it works. Is it best to remove the leaves and the entire stem close to the main stem or just where the leaf meets the leaf stem? Do I need to do anything to the open wound where I cut the leaf off? Also, is this soil born and would mulching heavily with straw help prevent it or is more airborn? I am not going to worry about it this year in terms of straw. I did lightly mulch my garden bed with straw. Perhaps double up on it next season.

Also, how long is a little while in regards to letting the milk/water solution sit out? A few hours? Half a day? Just curious. Thanks!

[rainbowgardener]

Yes, it is soil borne and yes mulching helps.

It's not rocket science about the milk, but more or less a few hours. Not to sour it, just to let the bacteria get active again after being refrigerated.