Ask a Question
Notify Me On Question Update
Email this Question
My squash plants turned white and wilted this summer. What happened?
Rate This FAQ
Your squash plants were infested with a disease called powdery mildew, which can be common in
Initial infection occurs via airborne spores from neighboring plants. The disease can develop very quickly once infection occurs, and is first visible on the shaded undergrowth, where leaves are dense, light is low, and humidity is moderate. The infected leaves will turn yellow, wither, and die.
The best way to manage powdery mildew in the future is prevention. Once infection has occurred, there is no way to “cure” that plant. Use powdery mildew-resistant cultivars of squash and other cucurbits. Examples include ‘sungold’, ‘sunray’, and ‘success’ summer squashes, ‘payroll’ and ‘ambassador’ zucchinis, and ‘table star’, ‘bugle’, and ‘celebration’ winter squashes. In fall, remove and destroy all infected plant material—do not till the debris from your vegetable garden into the soil. In the spring, start your plantings in a healthy, rich soil, and use wide spacing. During the growing season, improve air circulation around the plants by keeping the area weed-free, and avoid over-head watering and excessive fertilization.
Monitor your plants throughout the summer for infection. If you notice any spotting or curling of the foliage, or circular white patches on the leaves, remove the leaves or plant. At this time, start applying preventative fungicide sprays every 2 weeks. Examples include neem oil and sulfur. Research has shown that a combination of baking soda and horticultural oil can prevent infection (1 tbs. baking soda and 2.5 tbs. oil in one gallon of water).
Submit Your Suggestion
Other Questions In This Topic
- How many ears of corn grow on one stalk?
- A look at gardening catalog terms
- I have a reliance peach tree, 3rd year in the ground, and this year I noticed almost all of the branch tips were black, down about 3 inches. Some of the leaves started to brown spot and turn yellow, eventually falling. Also some of the branched produce fruit, but no foliage, the fruit is very weak and just falls in a light breeze. What can I do to correct this ?
- What is the secret to getting carrots to germinate?
- Moved to a new location in Riverton and started a garden. This spring I added compost and steer manure. The garden is watered using secondary irrigation. The leaves on the beans, corn, and strawberries turn yellow with a burned look on the outer edges of the leaves and then the plant dies. The tomatoes and melon plants all seem to be doing well. Any idea's?
- Is it possible to eradicate puncture vine by sterilizing the soil with solar energy through plastic or glass?
- I have just discovered an ant colony in my outdoor herb pot. I noticed soil build up around a couple of the herbs, thyme and rosemary and also soil build up around the drain holes. This pot is 20 inches across and 15 inches deep. How can I get rid of the ants without damaging the herbs or poisoning my family? Thank you.
- I would like to fertilize for weeds, but it has been so hot lately. Is there anything I can do this time of the year to kill weeds in my lawn, and if so, should I use granules or a spray?