Combating Powdery Mildew

The rainy season continues.  In the Month of June we had a little over 15 inches.  So far this July we have had 13 inches (not counting today) and still a week left to go.  Rainy season means the biggest gardening task is combating powdery mildew.

Powdery mildew is a disease caused by the fungi Erysiphales.  It is a real problem when the humidity and heat rise and will significantly reduce the harvest of your garden. 

The bad news is that I have it on some of my okra in the aquaponic gardens. Because of the fish component in aquaponic gardens, you must be careful that what ever you place on the plants will not harm the fish or the fish's environment.  The good news is that it is fairly easy to combat with non-toxic substances like baking soda. 

Every day for the last week or so I have said I need to treat that powdery mildew, but the rains have beaten me every day. So this morning I got an early start and before it rained, I mixed a solution of  2 teaspoons of baking soda into 1 cup of water.  If you need to make a larger batch, that is a 1:24 ratio of baking soda to water.  Here is a picture of the ingredients and tools (along with the morning's harvest of okra).  I like to harvest before I do any treatment.

Baking soda is alkaline (that means it has a high pH) and anything with a high or low pH will kill mold.  Powdery mildew may have a fancy name, but it is just mold.  Because I want the alkaline mixture to get the mold but not mess with the pH of the fishes' water, I applied it with my basting brush.  If I were doing this in a soil garden, I would make a big batch and just spray it on the leaves.

As you can see, this okra is doing really well.  The leaves are huge!  But they do have powdery mildew.  I

Okra on DWC raft

have been eating from the okra plants in the aquaponic gardens for about 2 weeks now.  The okra plants in soil have just started to flower.  Most of the gardeners I know in South Florida take the rainy season off. They are all amazed that I am able to grow anything right now, even though it is mostly okra and purple hull peas.

Speaking of purple hull peas, would you look at these beauties!  If you are not familiar with this plant, it is a legume and produces a shelling pea.  The pods start off green and then turn the most beautiful color of purple as they ripen.  The taste is a bit milder than a black-eyed pea,

but they do have a black eye.  It is a plant that used to be common (like kohlrabi) but has fallen out of favor.  I am hoping that the new interest in heirlooms will bring back the popularity of this plant.

The one thing that really likes all this rain is the lemongrass.  I can't cook with it fast enough to keep in in check.  If you have any ideas for cooking with lemongrass please share them. Because it is growing like mosquitoes with all this rain.

Speaking of which, I just finished treating and taking pictures when I heard the first rumble.  When I look around this is what I see!