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Bee balm mildew issues

Posted by stottlar1 6 (My Page) on
Tue, Aug 14, 07 at 22:15

Hi all,

I planted two beebalm this year and they grew to about 2 1/2 feet -3 feet tall and got a few blooms early july. Then the leaves got the white mildew spots on it and now they kinda went dormant and look ugly. Is there any way to reverse this mildew disease or do I have cut them back in the fall and wait til next year? Please help.


Follow-Up Postings:

RE: Bee balm mildew issues

that is one of the reasons i quit growing it ....

besides. i moved and forgot to take some with me.. lol ..

make sure the leaves are dry at night... PM thrives in damp, dank, hot darkness of summer nights ... so making sure the leaves are dry before dusk helps ...

as will increase of air movement at night ... probably helping dry wetness ... take a walk in the dark . and see if any areas actually have some air movement ...
research organic sprays for PM .. prevention is the key ... once its there.. its too late to stop it.. i think its as easy as baking soda and water ...

research resistant versions of the plant ...

good luck


RE: Bee balm mildew issues

The tricky thing about powdery mildew is that the spores are capable of germinating in high humidity conditions and do not require moisture on the leaves like other fungi. There are some nights when you will get these conditions even if you are careful about watering. Your choices are to plant a mildew resistant bee balm (if there is such a thing), replace it with something else, treat with a fungicide, or live with the damage. PM doesn't often kill plants and the next spring they will grow new shoots and leaves next year. There is a baking soda fungicide that you can make at home that some folks say works well on PM. Mix 2 Tbsp. baking soda, 2 Tbsp. Horticultural oil, and a few drops dish soap in 1 gallon water. This can kill the spores and prevent damage but doesn't cure the plant once PM has started. It is best to treat with this before or as soon as you see any symptoms, not when it is severe.

RE: Bee balm mildew issues

There are numerous "recipes" for this baking soda mixture and the one I have used for many years is simply 1 teaspoon of baking soda in 1 quart of water and that is sprayed on the affected plants every 5 to 7 days until the PM is gone. I have never found it necessary to add any kind of oil and some research has found the oil in this spray will do more harm than the PM.
Another spray that is just as effective is a 50/50 mixture of fat free milk and water sprayed on the same schedule.

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