My late-planted home garden cucumbers have been coming into the kitchen for three weeks now. The fridge contains a small pile of them, and I harvested more today, but the cucumber bonanza is nearing its end. The older cucumber leaves have spots/lesions that look like downy mildew; the leaves that still are unspotted and beautifully green droop in the afternoon sun. The droop makes me think that the plants have another disease, in addition to the mildew.
There is a bacterial wilt disease for cucumbers that is carried by cucumber beetles. I have checked the plants — leaves, stems, and flowers — very closely, and I have not seen these beetles. I have seen several bumblebees, some brown skipper-type butterflies, a few flea beetles, tiny snails, ants, a tiny native bee, a jumping spider, and one squash beetle on the plants, but those critters are not known to carry the bacterial wilt disease.
It is possible that cucumber beetles are very good at hiding. When I finally pull up the plants, I will check the stems for the white stringy goo that is a sign of bacterial wilt (as seen on the Missouri Botanical Garden page on bacterial wilt).
Meanwhile, I have a small basketful of cucumbers in my kitchen. Some of them will be peeled before we eat them, because something else has scraped the outer part of the skins. If I had found cucumber beetles, I would have suspected that they caused the damage. Since I haven’t seen those beetles, and since squash beetle damage looks different (remember the semicircular troughs?), tiny snails are my current top suspects.
It is hard to say whether the cucumber part of my late-summer-garden-experiment is a bust. The harvest seems short (three+ weeks), but we have a lot of cucumbers. The zucchini part is definitely a bust. There is zero chance of getting zucchini from the sad plants in the half-barrel garden.
Of course, the pepper plants continue to grow and make peppers, unmarred by disease. Some stink bugs have found them and blemished the skins a bit, but the peppers are all still good enough. The late-planted basil will be big enough for pesto soon. Chicory is looking good, too, and so are the carrots and assorted radishes.
I will transplant the rest of my cool-season seedlings into the garden this week. Currently, they are in a flat, where I planted them in late August. The new crops are kale, spinach, beets, cilantro, and lettuce. Those will all provide food for our kitchen in the cooler months ahead.