Q: Diseased Squash Plants
PVFS Customer question – PVFS employee answered
Question:
Last summer all four of my squash plants came down with a whitish-gray spotty/moldy disease. They grew beautiful and healthy for most of the summer but several weeks after the disease set in, they started to shrivel and die. I’m wondering if anyone can give me some insights as to why this happened and also if its something that is likely to happen this year and/or how I can prevent it.
Thanks so much!
Answer:
The symptoms you described could be a few things. My first thought is Powdery Mildew, or maybe Botrytis. You might consider consulting with your local Master Gardeners office or nursery in more detail. If it is one one of the two I mentioned, you could increase the air circulation around the plants (plant them farther apart, thin the leaves, etc.). Compost tea is a great thing to use if you have local access. It will increase the overall health of your plants and soil, and inoculate the leaves with microbes to battle fungus.
Hope that helps!
Thank you for growing organically,
Tags: botrytis, grey spots, mold, powdery mildew, White Spots
July 2nd, 2009 at 4:44 pm
What should one inoculate the leaves with? Neam oil?
July 3rd, 2009 at 1:36 pm
The compost tea itself would act as an inoculant, since it contains beneficial microbes that fight fungal diseases, etc. An oil based spray would help if it were a fungus such as Powdery Mildew, but be careful about spraying oil when it is hot and sunny. Here’s a great link on the subject of Powdery Mildew: http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7406.html. Check it out to see if that is indeed what you are dealing with.
July 8th, 2009 at 8:02 am
Thanks for the reply. Is it OK to use worm compost tea or strictly regular compost tea? I have loads of the former, less of the later.
July 8th, 2009 at 9:23 am
Worm casting tea is great stuff, but I’d say to also use a broader microbial tea such as what you’d get from a high quality Compost in the brewing process.
Check out the “Soil Foodweb” website: http://www.soilfoodweb.com/03_about_us/approach_pgs/a_01_benefits.html
for information on the different types of tea there are (look on the left sidebar “Understanding Compost Tea”).
July 9th, 2009 at 9:08 pm
We side dress with compost, use a foliar seaweed or fish emulsion spray, and prior to planting cover the area with black plastic to “cook” the soil which seems to reduce our disease problems. The only problem we ever seem to have is with squash vine borers and have never found anything that works other than physically removing the larvae from the stem and applying rotenone. We also seem to have less bug trouble when we plant nasturtiums around each summer/winter squash plant.