My cucumbers have been obliterated by cucumber beetles in the past. I tried clove oil traps once, but it didn't work well enough. (Though I probably got the traps out too late in the season.)

This year I'm growing Little Leaf. It doesn't need pollination, so it can be left under row covers 100%. We'll see how it works. As long as I can keep the beetles out, I might get more than just one or two cucumbers.

Here is a link that might be useful: Little Leaf

What has been successful for you?

Well, Jim, one thing has been successful for me on a slightly different situation. This situation concerns squash bugs. I made a concerted effort in the fall of 2008 to kill all squash bugs near the end of the season. This involved examining all remaining leaves and fruits of squash in my garden and ,yes, my neighhbor's garden and killing EVERYONE of them. This seemed to work very well.

Now as for cucumber beetles...they are a harder battle. You will often notice the first "flight" of beetles arriving sometime in May. They arrive suddeningly and will start devouring young cucurbit seedlings relentlessly. Kill them in any manner possible to keep them from laying eggs in the soil to hatch out the next generation.

How much this helps will depend on how good a habitat your neighborhood is for additional beetles and also if other species of cuke beetles are wind blown in later and also if there are corn root worm beetles in your area.

The beetles become active when ambient temps are around 65 degrees.

I am still working on those traps. I'll order the red dye online and compare results against using the dental disclosing tablets as the beetle killer. I've begun Caserta zucchini squash to use as the lure instead of clove oil. Apparently the beetles like it so much that even though it was an all-America winner one year, most people don't want to grow it a second season. The beetles flock to it.

I'll harvest the zucchini any size, cut them in half the long way, and dip them in a dilute solution of the dye. Then place them in the garden.

I am determined to see if I can find something that actually works without breaking the bank!

Anney,

Would you post a link to a post where you describe the most recent version of your traps? It would be handy to have it for easy reference in this thread.

Jim

Here's 3 suggestions in order to never get cuc beetles:
1. Count Fair picklers
2. County Fair picklers
3. County Fair picklers

:) I was forced into growing this pickling cuc because every year all the others were destroyed by wilt. I've been growing these for about 20 years, and they never, ever get beetles. I get them from Parke Seed.

Jim

That thread seems to have disappeared into outer space along with hundreds of others because of the problems GW has had with its software.

Maybe the three links below will be useful until I can do an update.

This link lays out the principles for devising a lure for cucumber beetles along with a poison of some kind that will kill them when they feed on the lure: Cucumber beetles "Bitter End". The lures attract and the poison kills only cucumber beetles, no other insects.

In the past I used Sevin in cups as the insecticide along with a mixture of tayuya powder as a cuke beetle lure, ordered from the internet. It worked very effectively, and even though the Sevin never went into the garden or on the plants, some people wanted another beetle killer that was not as potentially poisonous to the environment. Red dye #28 has been successfully used as an insecticide that works on cucumber beetles, as the first article discusses. It is phototoxic to the beetles and kills them in a matter of moments after they've fed on the lure impregnated with the dye. The dye is sometimes used as the red color in dental disclosing tablets and can also be bought in its pure form, though it isn't cheap.

Since any number of cucurbits are very attractive to cuke beetles, the following link is useful because it contains a ranked list of plants that attract cuke beetles and can be used as a lure: Cucumber beetle ranking of cucurbits.

This year I'm trying Caserta zucchini squash, and those who are interested in trying to eradicate the beetles this way can use any of the cucurbits as lures that are ranked high for beetle attractions. Just cut the fruits and impregnate them with the dye in some form or with the Sevin. Just be sure to set the fruits on something in the garden that will protect the soil from exposure to the Sevin. If you use the dye, you don't even need to worry about that.

The lures should be placed first into the garden, somewhat away from the curcurbits (cukes, melons, squash, etc.) that you want to keep the beetles from.

You should also note that NO insecticide will kill every one of the pests you're aiming for. You just want to keep them under control enough that they don't decimate your crops. So if you see a few of the beetles and are afraid the process isn't working, they may have just flown in from elsewhere. They tend to fly northward high in the air, and unless you already have them in your soil or in the vicinity, they'll probably find your garden.

And just for information... This link claims that cuke beetles do not seem to be a problem when gardens are grown in sandy soils: . Some people in coastal areas don't have any problems with them at all!

As I say, I'll do an update on the process, though it's too bad that the other posts were lost. A number of people had discussed how they handled the lure-poison principles and how it worked or didn't work for them. Most used clove oil as the lure, which attracts only female beetles. I suspect other lures are more effective.

Jimster, why not grow them in a hoophouse until they bloom? They will be early, and protected. I do not mind losing the plants in August either, because by then the garden is in full swing. To me cukes are important in early summer, so the hoophouse method suits my preferences.

catherinet,
I can't argue with you about your solution. I resent not being able to raise any variety I please, but yours is a good option. Better CF's than no cukes at all.

anney,
You have been so diligent and smart about this problem. Nobody else on this forum has presented such thorough research on any topic.

Plants can take up dyes with the water they drink. For example, white cut carnations are made green for St. Patrick's Day by putting green dye in their water. How about watering cukes with water containing Red Dye #28? Perhaps doing that with an early crop to protect a later crop or to reduce, even eliminate, the resident population.

"You should also note that NO insecticide will kill every one of the pests you're aiming for. You just want to keep them under control enough that they don't decimate your crops. So if you see a few of the beetles and are afraid the process isn't working, they may have just flown in from elsewhere."

I'm sure that is true in most cases. However, I and others have eliminated Mexican Bean Beetles for all practical purposes by using the predatory wasp, Pediobius foveolatus. New ones may fly in but I haven't seen any yet.

I haven't read the article you linked the title of which indicates that cucumber beetles aren't a problem on sandy soils. My reaction to that is BUSHWAH! I live on a pile of sand surrounded by ocean. I'll read it when I have time to waste.

glib,
That's what I had in mind with my Solution #3. It may be the most practical one.

Jim

I grew County Fair cukes for years and loved them--until they started to develop downy mildew--two years of it, first year in a drought, second year a cool, wet summer. So I'm forced to try something else this year. Also, I have very sandy soil, but still see cuke beetles.

glib

Do you grow non-vining cukes? How would you cover cukes that have begun to climb a trellis?

Apparently timing is just about everything with cucumber beetles, so if you CAN keep them off all your cucurbits for a couple of weeks, you should be good to go for their first life-cycle unless your neighbors have them. Depending on your geography, several generations can reproduce in a season.

I used to grow County Fair, which is early and makes cukes before succumbing to the beetle, and it does climb. I am switching because I finished the pack and I want to try something else. Anyway, I let it sprawl, but once uncovered it finds the trellis and it will climb maybe 3 feet before kicking the bucket. This year I may try to train it all all up the moment it is uncovered, the tomato ties I have are quite gentle on the plants.

Cucumber beetles and squash bugs are two of the worst pests in any garden. As a certified organic grower, the strongest "control" in our arsenal is 1% Rotenone--which will kill most anything except adult squash bugs and cucumber beetles (and ants--I've actually had ants live in 1% Rotenone powder).

The best method of control of any pest is a "trap" crop. Sometimes you have to forfeit growing most cucurbits for a season if you're so infected with cucumber beetles or squash bugs that you simply can't continue.

Of course a trap crop is a small crop of the type preferred by the insect you're trying to eradicate. Anney mentioned the squash that cuke beetles seem to be most attractive in her area, so she should use that. Do a small planting to attract the beetles to that area--it need only be 4 feet by 4 feet, or 10 feet by 10 feet, whatever suits you. When all the cuke beetles in the world are feeding on the trap crop, do them in with whatever suits you and you feel won't destroy the universe. I use pure ethanol. Do a succession of these small trap crop plantings, and at the end of the season, you'l have made a horrific dent in their population. (Unless your next door neighbor is working against you with his crop of cuke beetles allowed to run amuck.) It hurts to have to sacrifice crops you love to eat while your eradication process is ongoing--but it's sometimes necessary, and I've had to do it in the past. If you research both insects I mentioned, you'll find they overwinter in trash and debris and litter--and of course in all this stuff which is in the woods nearby, which makes it difficult--but garden cleanly and don't have junk lying around to give them instant access--leaves, old bales of hay and straw, old mulch, etc., all the things they love to hide in over winter.

Good work Anney, and others, who are trying to solve the problem. I'm an organic market grower, and some years I have to leave a 10' by 10' growth of cantaloupes or watermelons to herd up all the squash bugs and cucumber beetles that were on 5 acres of cataloupes and/or watermelons, then kill the thousands of those insects that congregate on the small planting. That's the beauty of a "trap" crop. I can either spray 5 acres--or I can wait until the planting is over and leave a small trap planting where I can kill them all as they flock to it. It makes a big difference in time, energy, and money spent.

I have many problems with cucumber beetles in my garden as well. I am wondering if anyone out there knows what time of day the beetles are least active. Most insects seem to have a time period where they rest or are sluggish (i.e. early morning, late evening, night). If that's true for cucumber beetles too, I'm thinking of growing mine under row covers and removing the covers to hand-pollinate during the time of day when the beetles are least active (so they don't fly into the plants as soon as I raise the cover, then feast happily on my plants under the row cover all day).

The best way to get rid of them is as I mentioned with a trap crop. But to answer your question, they're activated by heat. The hotter it gets, the more and the faster they fly, and the more difficult they are to catch and kill by hand. At night, they layover in squash flowers, down inside growing corn (and they'll even eat the tassles off the tops of the stalk that haven't even exposed themselves yet, but are growing, hidden, down in the center of the corn stalk). Of course they hide in all cucurbit flowers, particularly cucumbers and squash, but also cantaloupes and gourds and watermelons, etc.

I've never had the patience--or that small a crop--where I could cover them and hand pollinate, etc. But some growers do--even those who grow on a large scale use Remay and other lightweight row covers. I tried years ago, but it's a real chore. The stuff is relatively expensive for starters, and extremely difficult to remove and store, to use another year (as the manufacturer always states that you can do). It's so lightweight you can almost spit through it--and you can see through it--so it snags on everything, and holes are easily torn in it. I hate it. (Sorry Remay manufacturers).

I've been using mid weight row covers for years--not the lightweight ones which are indeed fragile. I use them to protect strawberries from frost, all my cole crops from the butterflies, and late, fall greens from frost. I reuse them and have never had a problem of heat build up during the summer.

Folks,

I'm prepared to cover my cucumbers this season and grow Diva cucumbers which do not require pollination. However, will last years cucumber beetle eggs simply hatch under my covers?

Thoughts?

Doc

I think you have to go under plastic, under fabric or spray killer toxins to beat these devils. They attack my crops and i just stopped growing quite a few plants.

I like the trap crop plus cover solution. For the home gardener, that means having some wasted space but let me
point out a few simplifications. First, you can reasonably grow cucurbita as a ground cover, say, in the front yard in the flower beds, or even as a specimen for bush zucchini. They are nice enough plants and no one will mind if the daisies get sprayed with Rotenone. Second, you can save seeds from a single squash or melon and you basically have enough to trap crop for the whole year. You could even buy the melon at the supermarket. It is probably best to use young, pre-flowering plants so no pollinators get killed. I only have to figure out how to get free seeds that will be attractive to the beetles, and how to start an early enough trap crop. Maybe plant the trap crop under the same cover as the crop, but let the vines out through a crack?

I haven't been able to grow cukes the last two summers either. So this year I'm trying something new - 3 parthenocarpic types that I'll cover with the lightest agribon - Diva (slicer), Cool Breeze & Rocky (both mini picklers).

The tricky part is going to be covering them well up the trellis, but I think I may be able to do it since I have a rectangular metal trellis that leans up against a fence. My plan is to put velcro on the sides and top of the fence around the trellis, then velcro the cover tightly to the fence. I'll bury the bottom edge in the soil.

Here's a pic of some of my sad, diseased cukes from last year so you can see the kind of trellis I have. {{gwi:43599}}From Garden 2009

I hope it works, I love cucumbers!!

I went googled and just realized what I used to mistake as yellow ladybugs were actually cucumber beetles :-o

They were not serious during summer time here. But after reading the horror stories here, no more mercy for these little guys.