Ask Jack: Dealing with Mildew

on June 14, 2016

One of the most common problems in the garden is mildew. If you’ve grown summer crops like cucumbers, squash, or zucchini in a humid area, chances are that you’ve dealt with mildew a time or two. Here are some answers to some common questions about dealing with mildew:

Q: Should I remove the leaves?

A: Don’t pick the leaves. Treat the problem.

Q: Will the plant still produce?

A: Yes, but progressively less and less depending on how invasive your strain of mildew is and it’s growing conditions. By fall, it’ll be useless if left untreated.

Q: Do I need to change the soil?

A: Not typically. But, if you have a severe case that has impacted the soil and it’s covered in mildew, I’d suggest replacing at least the top two inches. You also don’t have to sanitize or clean the GreenStalk container for mild cases.

Q: How can I keep it from spreading?

A: Well, there are a few things you can do. Don’t fertilize unless using a slow release fertilizer like osmocote. The key here is you want to promote steady growth. The disease feeds on new growth so applying a fertilizer in spurts creates more new growth at one time and the plant struggles to protect them. Move plants away from shade – a handy asset to growing in a GreenStalk. Water plants in the morning or in the afternoon – not in the evening. There’s been studies to show treatments with milk (40% milk + 60% water), baking soda (1 teaspoon per gallon of water + a little dish soap) work. Mix in a spray bottle and saturate leaves daily.

Q: What causes mildew?

A: I could get into the science of it, but there are many online resources available to you. It’s difficult to avoid. What you need to know when using a GreenStalk to prevent it is 1) space out your GreenStalks four feet or more a part 2) be observant 3) treat quickly.

Q: How common is it?

A: Very common, especially in high humidity areas. We’re in Tennessee and it qualifies as high humidity so we see it a lot in our home gardens. But you can use the treatments we suggest anywhere in your garden, not just in your GreenStalks.

Q: Any special tips for avoiding it/dealing with it in the GreenStalk?

Powdery Mildew likes humidity. Keep four feet between your GreenStalks and make sure there’s good air flow for your plants. If you’re in a high humidity area or already have a problem with Powdery Mildew, it would be a good idea to consider that when choosing what to plant in your GreenStalks. Plants highly susceptible to the disease should be grown in moderation together.

Q: Does it only attack cucumbers?

A: No, depending on your area it can impact flowering plants, squash, beans, peas and many more. There are different strains of the disease that impact different plants. Just because it’s on your cucumber plants, doesn’t mean it’ll infect your flowering plants beside it.

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Happy Gardening!

GreenStalk GrowerAsk Jack: Dealing with Mildew

1 comment

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  • sri A - August 29, 2020 reply

    Can i grow Tamatos, Bell Peppers, Okra,cucumber in one green stack vertical planter (5 tier). Is it possible

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