We have already had a taste of the high heat and humidity headed our way in July and August.

Usually when the humidity arrives, so does powdery mildew.

Almost all of the phlox and several of the cucumber plants are exhibiting evidence of this particular type of fungus.

Take heart, there is a cure for the unsightly malady and we’ll get to that.

First, it’s past time for a true confession.

Many years ago, we were lucky enough to be one of the gardens selected for the county Garden Tour.

During escorting a number of visitors, I was asked: “What do you do to manage powdery mildew?”

I said, “I’ve never had the problem so I don’t know how to answer your question.”

Later in the evening, after everyone had left, I was walking around the gardens and much to my amazement, powdery mildew had magically infested a beautiful stand of purple phlox.

It dawned on me it was at this very location the lady had asked about how to deal with it.

I was both embarrassed and humbled by the incident.

So to that guest, if you are still reading these articles, here is how you manage powdery mildew.

Sorry it took so long.

The best you can achieve is to keep from getting the mildew to begin with.

How do you do that?

Choose plants which are resistant to the mildew.

Plant catalogues and the labels attached to plants sold by local vendors often have “resistant to mildew” in their descriptions.

Even buying the resistant types will not prevent your plants from developing the powdery plague.

Since humidity is one of the necessary ingredients to producing the fungus, try planting in sunny locations where humidity levels will be lower.

Also, increasing air flow around – in – and through your plants will lessen the occurrence and spread.

Some gardeners say by watering from above the fungus particles may be dislodged.

I’m not sure this technique will help; but, at this point in the battle, one can’t be too picky about defensive measures.

There are fungicides specially prepared to fight the unsightly critter and with their use, you introduce chemicals into your garden.

If the chemical addition isn’t a major concern to you, then by all means apply the fungicide.

However, if you are open to other alternatives, here is a recipe I have used since that long ago Garden Tour: one tablespoon of baking soda, one tablespoon of vegetable oil (to help the solution stick to the leaves), one teaspoon of dish detergent all added to one gallon of water.

Stir gently so as to avoid a bunch of bubbles from the dish detergent and then add to a spray bottle.

Apply to the tops of the leaves and reassess in 10 to 14 days.

If you have a specific question for Art Kammerlohr, write to 370 NW 121 Road, Warrensburg, MO 64093, or email

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