If you are an avid gardener and have been for some time, chances are that you’ve encountered white mold. White mold is a beast, and to put it bluntly, it makes me crazy. It’s a fungal disease that can leech onto almost 400 different plants in your garden: cabbage, lettuce, peas, beans, tomatoes. Few plants are safe from it and even winter won’t kill it! The icky mold appears on stems and leaves and pods and blossoms. They wilt. They yellow. They rot. They die. It’s not awesome.
And as if that was the worst part, it’s not! White mold releases spores when the weather is cool, and those spores are pick up by the wind and carried to other plants, infecting them. This is one time that sharing is NOT caring! And this is why it’s so important to catch white mold and destroy infected plants quickly. Here’s how:
Identify: This is a tough one because many plants exhibit symptoms of white mold differently. One of the first things to look for it on the stem. There is often a water-soaked part that look different from the rest of the stem. The plant as a whole will still look normal from above.
Some infected stems may appear to have brownish lesions on them that grow weird cotton-like growth out of them if the humidity level is high enough. You’ll also notice wilting at the base of individual stems with a tan-ish discoloration. You won’t always see white fluffy coating on the stems and the bottom of leaves, but it is common.
Control: Destroy affected plants immediately. Do not pass go. Do not collect $200. Just take them and trash them. Don’t compost them or allow them to be near any other healthy plants. If you have diseased plants, check your soil. If your soil is infected, remove as much of it as you can and replace it with clean soil. I’d do this as a precaution anyway since it’s hard for me to tell if the disease has spread to the soil and I’d rather be safe than sorry! If the infected plants are near other plants, I use a barrier, like a layer of mulch or plastic to cover the soil to help prevent the spread of disease.
Prevent: Here’s the most important part. Since plants can’t be saved once they’ve been infected, preventing white mold is the key! Here are some great ways to prevent it.
- Spray with a fungicide to help prevent the infection
- Keep your garden weeded, as weeds harbor and spread white mold
- Remove all crop remnants after your harvest, as the disease can develop in the harvest residue
- Use well-drained soil
- Space your plants to avoid crowding {I never seem to be able to do this!} 😉
- Avoid planting in areas with poor air circulation
- Water plants early in the morning so they can dry out by night
- Do not water the tops of plants, instead water the soil
And there you have some steps to help identify, control and prevent white mold. Have you dealt with it in your garden before? Do you have any tips for your fellow gardeners? Do tell! 🙂
~Mavis
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Cathy says
I remember baking soda and water mix could help the plant , pumpkin and cucumber, in my garden , not cure .
Robin says
Ugh – white mold/powdery mildew is half the reason I gave up growing vegetables on the lakeshore (Lake Michigan). I grew up in a gardening family 70 miles inland, and growing stuff by the big lake takes some adapting. There’s extra moisture/humidity, and cool weather in June as the wind comes off the lake for most of that month. My relatives’ inland plants develop faster.
Linda says
Thank You for this valuable information!
Diane says
I read a paper from a botanist in New Zealand. He reported using diluted milk against powdery mildew. Dilution ratio 1 to 3 parts milk to 10 parts water. He claimed that this had an anti-fungal effect as well as seeming to act as.a folliar immune booster. He was using it on grapes, said it was also good for black spot on roses.
I’ve used it on various squash plants with good outcomes. I like that it isn’t a “chemical” and who doesn’t have a little bit of aging milk in the fridge that needs to be used up.
Don’t go over 3 parts per 10, it’ll be rancid smelling if you do! Beware 🙂
Have a great weekend!
Jenn says
I do the same but also add a good heaping tablespoon of baking soda to the mix. It won’t complrtely cure the plant but more “knocks it back” so you can hopefully keep it alive until the harvest comes in.
Carla M Edwards says
Please read. Good information on controlling powdery mildew, which, I think, you are writing about. http://ipm.ucanr.edu/PMG/r280101011.html
Nicky says
I was told there was no need to destroy plants with powdery mildew. I was advised to remove the worst leaves, give the plants a good feed and make sure they were well and regularly watered. Last year my courgettes grew through it and I had a bumper crop. Really it was just cosmetic and a sign my plants needed a bit more TLC!
KATRINA FOURNIER says
I, too, had this last year and in years past. Mine grew right through the problem..