Perhaps one of the hardest vegetable insect to control in the garden is the cucumber beetle. They seem to show up every year, no matter what you do to mitigate them in the season prior. And these insects can really do a number on cucumber, melon and squash plants.
The beetles are about a quarter of an inch long with three black stripes or spots on yellow bodies. They emerge early in gardens, when temperatures reach the 50s in the spring. Often, cucumber beetles overwinter in garden debris or in other weedy areas.
When cucumber beetles emerge, they are programmed to seek out the color yellow, just like the flower blossoms on your cuke and squash plants. Once they find your young cucumber transplants or seedlings that are just coming up, cucumber beetles begin feeding and can cause a lot of damage along the way.
Though the beetles can really do a number on young plants, these insects are still a problem now, a bit later in the growing season, too. They can actually influence pollination by attacking the cucurbit flower and creating a situation where the fruits don't get pollinated properly.
More from Vermont Public: Quash The Squash Bugs And Cucumber Beetles
Along with that, these beetles can transmit bacterial wilt disease when they feed, which will cause your plants to look wilted even though they've been watered, and the plant will eventually die off.
Luckily, there are a handful of things to try and rid your garden of the cucumber beetle. You can start off by seeking out the right sorts of cuke and squash plants and prioritize finding disease-resistant varieties.
Another method to keep cucumber beetles numbers down is to hang yellow sticky traps (remember their affinity for the color yellow?). Look for the traps with a substance called "Tanglefoot." When the beetles land on the trap, they get stuck and die.
Other techniques to try are to approach gardening differently. You could rotate crops, cover your plants before they flower or even elevate plants up off the ground by using straw bales and planting directly into them.
As a last resort, you can try an organic spray like Spinosed. If you go that route, do so with great care: this treatment can be toxic to pollinators. Spray before the cucumber flowers are out, or spray in the evening when the bees are not active. And once it has dried on the plant it is not as toxic as when it's wet.
What is bugging this listener's bean plants?
Q: I try to keep my gardens as organic as possible, using companion plantings to help ward off pests. But do you think that the leaf culprit on the bean plants may be aphids or some type of beetle? And I have a bottle of Neem oil that is 10 years old. OK to use? Or if not, how to dispose of it safely? - Sue, in Killington
A: The holes on your bean plant most likely are from slugs and snails who have been enjoying the wet weather. When the bean plants were just emerging earlier in the season, they were feeding on your green bean plant's tender young leaves. You can manage slugs with a beer trap that you set out and the slugs go in for a sip and fall in and drown.
As far as the Neem oil goes, its shelf life is a year or two. In order to dispose of it properly, you could take it to your county's hazardous waste site.
How to control goutweed
Q: I came to the Vermont side of the Upper Valley in 2011. At that time, purple and white phlox was along all the roadsides. Now there's only goutweed. It seems the invasive has eradicated everything including Trillium and Jacob's Ladder. - Byron, via email
A: Goutweed, of Bishop's weed, is a perennial that has serrated green leaves with white edges and can grow to a couple of feet tall.
Goutweed is indeed an invasive plant. It grows quickly, thrives in shaded areas and can choke out native plants. The plants can be eradicated by pulling them out repeatedly, and ensure you're pulling out the rhizome or root system, too.
However, some of the variegated varieties of it are very attractive and still for sale. If you purchase and plant them, know which kind you've got as certain goutweed will take over quickly and spread onto roadsides.
If you choose to plant goutweed, choose to grow it around trees or in a place that you'll be mowing regularly. You could also plant it in an area that is blocked by a building or asphalt where it can't spread.
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