Has anybody tried baking soda to prevent powdery mildew

Joopster(5 (Chicago))October 1, 2013

Has anybody tried baking soda to fight powdery mildew on hydrangea? Did it work?

1 tablespoon of baking soda
� teaspoon of liquid soap
1 gallon of water

Thank you for reporting this comment. Undo
luis_pr

I used a milk/water mix on one of my Crape Myrtles some time ago. Unfortunately, I then forgot to recheck if that mix helped until more than a year afterwards! LOL! Hee hee hee!

    Bookmark   October 1, 2013 at 12:07PM
Thank you for reporting this comment. Undo
CreatedToCook(CA 10a/SunsetZn. 22)

I haven't tried it but mine are suffering from powdery mildew... So I may need to give it a try. Will let you know if I do and if it works.

    Bookmark   October 1, 2013 at 5:19PM
Thank you for reporting this comment. Undo
gardengal48

This is essentially the same as the Cornell Formula, a fungicide developed by a plant pathologist at Cornell University some 30-40 years ago. Unfortunately, via word of mouth and the Internet, the precise formulation has morphed into something other than the original and these 'revised' recipes may not have the same impact and can even become harmful to plants.

The correct formulation is 2-3 tsp. of baking soda (sodium bicarbonate) to 1G of water with 1 tsp. insecticidal or castile soap (not dish soap or detergent) and/or 1 tsp. horticultural oil (vegetable oil works as well). The baking soda actually alters the pH of the leaf surface, making it inhospitable to the survival of the fungal spores (milk accomplishes much the same process). The oil and soap act as surfactants, helping the mixture adhere to the foliage. You do not necessarily need to add both, however. It is as effective as any other commercial fungicide when mixed and applied properly

Newer research has indicated that potassium bicarbonate is somewhat more effective than the baking soda - baking soda just is a lot simpler to get one's hands on. And it is important to remember that like virtually all other fungicides, this is a preventative, not a curative. It can help to keep the disease from spreading to unaffected foliage but will not remove or eliminate any existing problems.

And it is always a good practice to combine a spray for powdery mildew together with good cultural controls that limit the incidence of the disease in the first place.

    Bookmark   October 1, 2013 at 5:23PM
Sign Up to comment
More Discussions
Nikko Blue size
I planted a tiny bare root stick of a Nikko Blue Last...
NVL4
New 2015 hydrangea cultivars?
Anybody looking into what's coming in 2015. I thought...
plumism
Need help with hydrangea companions
Hello. I am putting in a new bed this Spring. It is...
suz9601
No Time To Winterize Endless Summer
I did not have the time to winterize my endless summers...
DDhydrangea
Can I prune hydrangeas and loropetalum now??
So we have some hydrangeas (blue and purple flowers...
hiddenspring
© 2015 Houzz Inc. Houzz® The new way to design your home™