Late Summer Woes in the Kitchen Garden #3: White Powdery Stuff on my Squash / Pumpkin / Melon /Cucumber Leaves

Remember when you planted those zucchini in the late spring? You amended the soil and gently tucked the young-babe-of-a-plant into it’s rich new home. You watered it carefully and cleared the weeds, fretful that it wouldn’t make it. And then it started producing fruit…

You were happy with the initial abundance but soon became overwhelmed and sick-and-tired of tucking zucchini into inappropriate dishes. A zucchini omelet is fine but how many of those does one really need each year? You stealthily hung sacks of the overgrown fruit on neighbours doorknobs and quickly ran away, feeling good for having given a homegrown gift but knowing all the while that you had just passed the ethical buck of wasting food to an innocent friend. Zucchini bread for all!

But now the zucchini harvest has declined. What was once a plant that constantly nagged you to the harvest is now looking destined for the compost pile. New growth is infested by a white powdery substance and older growth is yellowing, browning, becoming crunchy and falling off. This, my friends, is a well-known nemesis to the grower of cucurbits (the squash family) and several other types of vegetables. Pumpkins, winter squash, and melons are all susceptible. Warm, humid weather brings powdery mildew and we’ve had lots of that stuff this summer. The folks at the garden center definitely have a spray to sell you. It’s a silver bullet, they’ll say. In my opinion, there’s nothing much to be done. Organic sprays are largely ineffective and “conventional” fungicides are nefarious substances that require you to don gloves, a mask, closed-toed shoes (heaven forbid), and the fortitude to expose yourself to a toxin simple to save a plant that you once cursed for its productivity.

Instead, remove infested leaves and fruit after the morning dew has dried. COVER these in your compost pile or put them in a closed container and send them to the landfill. Some studies suggest that a light misting of water can help prevent the issue.

I just try to plant my cucurbits in the middle of March and get the most out of them before the mildew descends in June – mark your calendars for next year. Working with Mother Nature is always the best way to garden.

Leave a Reply

Your email address will not be published. Required fields are marked *