Cucumber Wilt
July 9th, 2009 · 6 Comments · Posted in garden
First the leaves wilt, then the plant dies
In the years since we turned our front yard here in the District of Columbia into a kitchen garden we’ve had few problems with pests or diseases. I attributed our good fortune to being fairly isolated from any large plantings of vegetables. How would the pests find us? I also figured we were just brilliant gardeners, using no chemical fertilizers or pesticides. We build a rich soil with compost, and our plants respond by being healthy to the point of impervious to any kind of attack.
Oh, we did have a blast of powdery mildew one year when we planted hard squashes and melons. They wanted to take over the entire property–they were taking over the sidewalk–until they started to look like a snow storm in September. We yanked them all and have completely abondonned the idea of growing our own winter squash or canteloupe.
This year has been a bit different. Maybe nature is having her revenge on us. First it was the rain. Day after day of wetness. And when it’s raining, the sun isn’t shining. The garden wasn’t getting enough sun. Our favorite Italian zucchini were rotting on the vine. Recently, we started to notice the leaves on our cucumber plants wilting. It couldn’t be from lack of water. We had plenty of that. So I didn’t pay much attention, the same way I don’t pay much attention when other plants catch a cold.
But the problem wasn’t going away. One after another, our cucumbers were coming done with something, and they were just wasting away, the leaves going limp, then shriveling into dry gnarls.
I figured the cucumbers had caught whatever had infected our zucchini. But since the symptoms were so very different–fruits rotting versus leaves wilting–I started an inquiry online. Sure enough, I think what we have here is a classic case of cucumber wilt.
The striped cucumber beetle carries the disease
This kind of wilt can also affect melons and other cucurbits. It’s usually caused by the striped cucumber beetle, seen in the photo above, which carries the agent–a bacteria–in its gut. (The spotted cucumber beetle can also be a carrier.) When the beetle begins feeding on the cucumber plant, it transmits the bacteria to the plant. Once the plant is infected, it’s a goner. You might as well pull it and toss it in the compost heap. The cucumber beetles will feed on the damaged plant. The plant will die utterly within a week or two.
During the course of the disease, the bacteria creates an ooze that blocks the plant’s veins. Even if it has plenty of water available, it will be unable to draw the water out of the ground. It dies of thirst. You can test for the disease by cutting a stem and touching the cut end with a finger. You will likely pull away strands of ooze. Or put the cut end into a glass of clear water. It will turn the water cloudy.
According to the University of Maryland Extension Service, organic gardeners can try destroying the cucumber beetles with botanical insecticides such as neem or pyrethrum. If you see any beetles, snag them and squash them before they infect your cucumbers. You can also cover your plants with row cover from a young age.
Me, I’ve already planted more cucumbers. We’re disappointed that our usual bounty of cukes this year will be interrupted. But we’ve already made two large batches of pickles. We’re just going to roll with it. In fact, in my latest seed order with Southern Exposure Seed Exchange I’ve requested a couple of unusual slicing cucumber varieties. Maybe this is one of those garden teaching moments.
Gasp! What’s Mr. Pickle going to do with an inadequate cuke supply? Very sad news indeed. Hope you have better luck with replacement crop.
Janet, I guess this is our Thelma & Louise moment, when the road suddenly falls away and no cucumbers. Usually we have too many. This gave me some time to think about it a little and work some new varities into the rotation. More to come!
oh I HATE those guys – them and the stink bugs (and squash beetles) – we had a terrible onslaught of both last year, so I decided to plant all my cucurbitaceas late to see if I could starve out the first generation. Hence me having no squash nor cucumbers yet. So far, I have been able to pick them off, but I still lost a few cucumber plants.
Yea, let’s go plant some more.
The same thing happened to some of my cukes here in the Ft Stevens community garden. The squash here has also really taken a hit. But on the funny side my english cucumbers are growing like gangbusters! Who knew?!?
Sy lvie, so far I have not seen a single cucumber beetle, but one of our gardening friends says she has. Another strategy is to delay planting the cucumbers to disrupt the beetle’s life cycle.
Audrey, I’m sorry to hear you are having similar troubles at Ft. Stevens. But misery does love company. I’m sure this will pass soon. I’ve already planted more cukes and more squash.
Do NOT Compost Bacterial Wilt guys!!!