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Cucumber Beetles

Credit: USDA
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Here are tips on how to identify, eliminate, and control cucumber beetles.

What are Cucumber Beetles?

If you find that the stems of your seedlings are being eaten off, yellowing and wilting leaves, and holes, you may have a striped cucumber beetle.

Cucumber Beetles are found throughout the US and cause much of the same damage as flea beetles do. They are attracted to Cucurbit vegetables, namely cucumbers, squash, pumpkins, and beans.

Often, the beetles leave their hibernating sites early in the season, and feed on seedlings right as they are emerging, often killing them. The larvae feeds on the roots of the host plants. Adults will also feed on the leaves, vines, and fruit of plants that survive, often making deep marks in the rind.

They hold another threat too: the can carry bacterial diseases and viruses from plant to plant, such as bacterial wilt and mosaic virus.

How to Identify Cucumber Beetles

Adults are about ¼ inch long and have a yellow and black striped abdomen and a dark colored head and antennae. Look for holes and yellowing and wilting leaves. Crop yield will be low; and plants will produce yellow and stunted fruits. The larvae are worm-like, white, dark-haeded, a have three pairs of legs on the thorax.

Often, the Cucumber Beetles alone will not kill the plants or cause major damage, but the spread of disease will. Adult cucumber beetles overwinter in weeds, garden debris and woody areas. The diseases they carry can also overwinter internally, and can be passed onto plants the next spring through fecal matter.

How to Control Cucumber Beetles

  • Inspect newly planted cucurbit plants for the presence of this beetle; be watchful when plants are seedlings.
  • Cover seedlings with row covers, though you rmust remove during blossoming time several hours each day to allow pollination.
  • If you till your garden in the late fall, you will expose cucumber beetles hiding there to harsh winter conditions and reduce their populations next year. Tilling has the added benefit of making the soil easier to work in the spring.
  • Where cucumber beetles are a problem, let the beetles come out of hiding and plant late. They have a knack for finding vulnerable seedlings. When yours are up and growing, the cucumber beetles will be gone, fooled into thinking you don't have any cucumbers in your garden.
  • Few insecticides can be used on cucurbit plants because they are very sensitive. They would need to be used when plants are beginning to emerge through the soil. Please contact your local cooperative extension for a list of approved insecticides for your area.
  • Natural predactors include soldier beetles, braconid wasps, some nematodes, and soldier beetles.
  • Once bacaterial disease has entered the plant, there's very little that you can do. If it's bacterial wilt, you'll see the leaves dry up and the plant will quickly wilt and die. Take prevention for next year as described above.
     

 

 

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Comments

Bug problems on my gourds...I

By Marie Martinez

Bug problems on my gourds...I am seeing the cucumber beetle and squash beetle on my gourds. Found several ideas here to try. But, I'm not getting flowers on the Luffa, and on the Bottle neck and Apple gourds, the flowers are drying up and dying or as the little female flower starts showing the hourglass shape, it's drying and dying off. What's going wrong?

When the tiny female fruit

By Almanac Staff

When the tiny female fruit shrivels and dies instead of developing, it's almost always a pollination issue. Do you have bees in the garden? Bees stay away if there are insecticides, rainy days, or extreme weather. You could always hand pollinate the female blooms. Just take the male stamen and brush it against the female in the morning when both blooms are open.

I see no evidence of cucumber

By Paul Karki

I see no evidence of cucumber beetles or larvae, but the plants grow beautifully for 25-30 days and then the entire plant withers and dies. The root is rotted completely except for some fibrous material which, apparently the pests or fungus cannot digest. Any other possibilities, or any suggestions?

That's unfortunate, Paul. It

By Almanac Staff

That's unfortunate, Paul. It sounds like a wilt, especially if there is no sign of beetles and the plants appear to thrive, until they fail fast. Fulsarium wilt survives in the soil for years. There are no chemical treatment for this; planting resistant varieties is the best advice.

There is also a bacterial wilt that can cause the plant to die off but it is carried in (yes, in) the beetles. They distribute it in excrement and the slow demise begins.

I put a yellow frisbee and a

By Ruthanne Campbell

I put a yellow frisbee and a yellow bowl in my garden with water and dish soap in them and every day I see floating cucumber beetles and other bugs!

Finally I found a solution

By Nino

Finally I found a solution for cucumbers bugs....dead,,,,, I got this product in USA it called :ECO SMART ORGANIC ISECTICIDE, it is safe.

I was wondering a little more

By tyne@kragnesfamilyfarms.com

I was wondering a little more about the flea beetle trick??

thanks for the tips, i

By brock ingham

thanks for the tips, i recently say a video of someone using a clove of garlic mixed with about 3 cups of water to liquefy then adding an additional 3 cups and letting it sit for a couple of days to ferment. once fermented mix with water (1 part garlic solution to 10 parts water). just about to make my batch now fingers crossed that it works.

We grow organically and are

By Cornflower

We grow organically and are always looking for effective ways of minimizing insect damage and over the years we have learned a few "tricks". Yes we plant the beans late for our area (south shore Nova Scotia)usually around the first week of July and miss the bean beetle cycle. For the cucumber beetle and potato beetle I place glass jars with about an inch of heavily perfumed laundry soap every 10 feet along the rows partially dug in to avoid spillage. Just poke a few holes in the lids for the scent to escape and we no longer spends hours handpicking these beetles off. It really does work. Just add more as needed. We still see the insects around the edge of the garden but the perfume does not allow them to find the plants you are protecting. Fleas beetles...till the soil and seaweed.
Aphids are dealt with by mixing sodium borate (borax) with icing sugar and place in small plastic tubs with holes near the base large enough for ants to get into. Place at the base of your apple trees and other plants affected by them. You will spend a lot less time picking off insects leaving more time to weed. :)
Remember not to mow around your fruit trees leaving your dandelions to bloom and attract the bees till your trees are ready to blossom out, then mow. We also encourage toads by placing inverted clay flower pots here and there. Happy gardening everyone in 2012.

I was wondering what kind of

By CGHPND

I was wondering what kind of detergent you use. How about dryer sheets? Would that work too?

Any strong smelling laundry

By Almanac Staff

Any strong smelling laundry soap will do. You can try dryer sheets.

I have found a few cucumber

By colman242003

I have found a few cucumber beetles inside blooms. Will this trick drive them away? I was wondering the same thing someone else asked...liquid or dry detergent? want to try right away before I get an infestation!

hi what type of laundry soap

By wayne desnoyers

hi what type of laundry soap do you use is it dry or liquid soap please anwser needed asap thank you

I am going to try this tip. I

By Debra Pretko

I am going to try this tip. I have had trouble growing summer squash as well as cucumbers. I have tried everything on the market and everything I have read this far with no luck.
I have been trying for 23 years. So here goes number 24.
Thanks :)

Debra, The stink bug is the

By Doug 2

Debra, The stink bug is the worst enemy of squash. First solution that has worked 100% FOR ME. OUT OF 9 PLANTS THIS YEAR HAVE PICKED AT LEAST 150 LBS. OF ZUCCHINI SQUASH. Two people, one on each side of plant. Take hose and flood stem of plant. They spend their time under the stem root. When they come up for air, squash them. I have killed at least 40 of them this way and none have had time to lay their little red eggs under the leaves.

I have never had the cucumber

By karen cass

I have never had the cucumber beetle before.I bought from a different com.now its invested.Im so upset I will try ypur advise.Im in Nova Scotia.

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