Luria
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Help- Powdery mildew

Hi:
Almost my whole garden died due to something I think is powdery mildew, now the disease seems to be trying to spread to 2 other plants I have in pots. Any idea on what can I do to eradicate this disease? Sulfur is not an option, I'm very allergic to it and the oils I read about I can't find them around here. Also can I start planting again in the soil that the infected plants died on?
Thanks
:)

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Kisal
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You can spray your plants with a mixture of milk and water. The mixture can be anywhere from 1 part milk to 10 parts water, up to half milk and half water. Any kind of milk will work, even reconstituted powdered dry milk.

IIRC, it's the lactic acid in the milk that does the trick, but I could be remembering that incorrectly. I can't find the link right now to the study about it.

Apply the spray thoroughly, until it drips/runs off the plants. Be careful to get both sides of the leaves, and spray the stems from all directions.

As far as I know, powdery mildew is not a soil borne disease. It's a fungus and the spores are spread by the wind.

if you could post some pics it might help identify the problem. Some insect infestations can be mistaken for powdery mildew. [url=https://www.helpfulgardener.com/forum/viewtopic.php?t=3724]How to Post Pictures & Photos[/url]

Good luck to you! :)
"Isn't it enough to see that a garden is beautiful without having to believe that there are fairies at the bottom of it too?" - Douglas Adams

Luria
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Joined: Tue Nov 29, 2011 3:46 pm
Location: Puerto Rico

Thank you!

I am not sure if it would be visible in a picture, most of the plants died already and the other has it really mild. But the plants look as if someone sprinkled the leaves lightly with baby powder and part of the leaves turned yellow and started dying. Then the plants started drying and died. We did get about a month of extremely heavy rain, specially during nights. I had applied some 20-20-20 fertilizer to my plants about a week before this issue started and i thought this was the problem but my other plants didn't died and this fertilizer is commonly used around here and it works for other people. I have some lil plants I need to transplant and I am afraid to loose them the same way :(
I checked on the milk solution and for the info I found it works very well, said it could be used in an up to 50% milk solution, from 10% sprayed about 3 different times, or 50% from 1-2 times.
Thanks :)
:)

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rainbowgardener
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It does sound like powdery mildew.

20-20-20 is very intense fertilizer. I don't use artificial fertilizers at all, but if I were going to use something like that, I would use it very sparingly and diluted. I do think it contributed to your problem. Putting a fertilizer like that on forces a lot of lush tender new growth, that is very vulnerable to whatever insects/ diseases are around.

Left to grow more naturally, plants can protect themselves from pests and diseases a lot better.
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Luria
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Location: Puerto Rico

Can I grow stuff without adding fertilizer?
:)

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rainbowgardener
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Need to clarify the question:

Can I grow stuff without adding nutrients? Depends on how rich your soil is to start with, but eventually the nutrients in it will get used up and you will need to add some. Organic nutrients include manure, compost, worm castings, mulch that breaks down to feed the soil, fish emulsion, seaweed extracts, etc etc. All of these give nutrients plants need in the form they need it, in slow release versions released gradually as they break down. They are conducive to the life of the soil, so build up the colonies of earthworms and micro-organisms that feed the soil and the plants. The plants can take what they need as they need it and grow naturally.

Can I grow stuff without (synthetic) fertilizer? Absolutely! My lush beautiful yard has never seen a synthetic fertilizer. Synthetic fertilizers are salts. They provide NPK and nothing else (no trace minerals or other nutrients, no humus or tilth for the soil structure etc), in huge amounts but not necessarily in forms plants can use best. They tend to kill all the life of the soil, so you have to keep adding more and more fertilizer. Over done they can burn your plants, even kill them, and even at "recommended" concentrations/ frequencies, they do what I said, force a lot of tender lush growth that is very attractive to insect pests and very vulnerable to pests and diseases.

It becomes a chemical addiction-- because all that lush tender growth attracts and is vulnerable to every insect in town, then you start feeling like you need insecticide, maybe more than one or repeat applications. Because it is vulnerable to diseases, you start wanting fungicides. Pretty soon you are living in a toxic wasteland....
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sunnyvalley
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Is fruit unsafe to eat from powdery mildewed plants? My zucchini has it, but is acting normal underneath the fuzz and producing ok-looking fruit.

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rainbowgardener
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The zukes should be fine....
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