What I have done is watch for them in mid May [here] when the old adults that wintered over emerge. They make a beeline for cucurbits...melons, cukes, squash, and such and start eating the newly emerged seedlings and then lay eggs around the roots of those half eaten seedlings so that the second generation that emerges now will have roots to feed on. It isn't enough to kill the adults feeding on the seedlings, but you need to dig carefully around them and kill those down in the ground laying eggs.

Ok, that doesn't help your situation now, but is something to remember. if you can stop the first generation, then you should have a lot less coming on now.

I know of no insecticide that is safe for all insects. Row covers or insecticides are the only options after you have or are going to have them....besides letting them go on. Sevin works well and if carefully used, is about the most effective. Do any spraying in the evening if there are blooms.

I have some Sevin, I will spray the base of the plant... they haven't bloomed yet. Thanks.

I don't use chemicals. For cucumbers, I had to resort to "County Fair" pickling cucs. They are bred to not have the bitter gene........which is what attracts the cuc beetle. This is the ONLY way I can ever have cucumbers. That might indirectly help you to decrease their total population in your garden. I'm sure that this variety of cucumber works. One year, the seed company must have sent me the wrong seed, 'cause it immediately got beetles and the wilt and died. The few cucs that survived were definitely not the County Fair variety.

I'm actually not even growing cucumbers... zucchini, acorn and butternut squash, and pumpkins. They were on the zucchini.

Peter, why would you spray Sevin at the base of your plants? That chemical is a contact killer , and will only affect insects that come directly in contact with the liquid while it is still wet.

Sevin is such a deadly pesticide that it wipes out the population of beneficial critters, creating the kind of environment suitable for an explosion of pests, such as mites and whitefly.

I strongly recommend the use of Surround WP , a kaolin clay product that is mixed with water and applied as a spray. It not only protects a plant from feeding pests, but also greatly diminishes their egg laying. I began using it during a really bad Japanese Beetle outbreak. It does help with the cucumber beetles.

Another huge benefit of the kaolin coating is that it will prevent sunscald on sensitive fruits and veggies, and greatly reduces heat stress.

It depends on how many you have and on how many plants. I have the SCB on my 8 winter squashes and two zucchinis. I patrol them every morning and do the grab and squish. The nice thing about the SCB is they come out in the morning sunshine to feed and mate, right out on top of the leaves where you can see them and grab them. And I always remove and destroy the spent male blossoms and unused female blossoms as the SCB tend to congregate in there. This works for my modest number of squash vines but may or may not work in other situations.

They are usually really slow moving in the early morning ( in my garden that is). They don't seem to be able to fly away but if I try to pick them off, they will let go of the leaf/petal and fall to the ground and get away. What I do is hold a cup of soapy water underneath so that, when the bug falls, it goes into the water and drowns rather then onto the ground. There are sprays but I don't like to use insecticides of any kind. You can reduce the damage if you hunt them every day. They seem to like everything but tomatoes in my garden but especially the zucchini and the open roses--they hide in the petals. Once you identify their favorite plants you can really reduce there numbers by targeting those particular plants. Where I am, the infestation usually last a couple of weeks and then after that they become less of a problem.

I don't have time in the morning. I have a very long commute to work.

I went scouting and sprayed the very base of the plants with Sevin, very carefully. It is what I had on hand and it works, and there were no beneficials to be seen.. pest activity was pretty quiet otherwise. There were lots of them hiding out under the cotyledons, and they have clearly been eating them. I even saw some mating and a squash bug too. Thankfully no SVB yet, I have been regularly spraying the stems with BT in hopes that will work.

My remarks to you were in reference to your "spraying" the Sevin at the base. I still wonder what you expect to achieve by that but your mention of cotyledons indicates that these plants are tiny seedlings.

Do you think that Sevin, either dust or liquid, is translocated through the plant to affect pests that feed on leaves or fruit? I'm just trying to understand.

They are not tiny seedlings. In my experience happy well fed plants usually keep their cotyledons well into adulthood. They are still fairly small though, especially a few of my zucchini are very small, and have not flowered yet. Which is to be expected given my location.

The cucumbers beetles are congregating a t the base of the plant, and hiding out under the cotyledons (and it appears eating them), where I sprayed. as I said in my post. I sprayed where the pests were. I am not sure what is confusing about it. I do not think this is unusual, either, early in the season. I get that you are against the use of Sevin, but it is my perogative and I believe I have used it reasonably.

I grow nasturtium flower and radish in between the cucumbers and I believe this helps a lot. A LOT. It's probably little late to do it now since nasturtiums usually are grown from seeds. The stores don't sell plants but the seeds are big and they grow fairly quick. I grow daikon radish summer cross #3 but I think any radish work.

I believe radishes draw small flea beetles and the like...probably not cucumber beetles. I have grown nasturtiums. They may help a bit though i would not depend on them a great deal.

Peter, I think you are being reasonable. Since this isn't an organic forum, I don't see why someone would jump at someone using reasonable methods. We are here to share and learn and learning to use a small amount of rescue sensibly seems good to me.

look into Spinosad, I've used it this year and have been very pleased

Thanks Wayne, I appreciate that.

It seems to have worked... we'll see for how long. I do not want to be frequently spraying Sevin, nor do I want to spray at all once the plants are flowering... which will probably be soon.

I will look into Spinosad, thanks.

I am not jumping on you at all for using Sevin. I have been honestly confused by how and why you were applying it!

I have honestly never seen cucumber beetles congregate at the base of the plants so was simply trying to figure the situation out. Clearly, your beetles are behaving in a manner I would not expect.

I thought that if you are going to use this chemical in your garden, I might be able to help you use it to get the best results. You didn't know that Sevin is a contact killer and that it is not effective once the spray dries. I know all about the dust, and that is quite different, obviously. The dust can kill critters until it's washed away. But you kept referring to a spray.

So anyhoo, best of luck to you!

Rhizo, can you back up that claim? I am not trying to be argumentative I just really want to know if it is true or not, and googling I can not find that info. I do know that depending on the pest it may need direct contact, or it can be eaten, including the spray as far as I can tell. In any case, it was apparently successful - for now. I will look into other options as the season continues.

My 2 cents for future control.

I've notice the last couple of years that cuke beetles Love spinach pollen. When I plant spinach seed on Labor Day (for fall a late harvest) the over wintered (oldest) spinach will bolt and bloom before my cukes get going. Cuke beetles seek out and congregate on the pollen spikes at the top of the old spinach plants. That's one of the few times I will use a sprayer with liq sevin to wipe them all out at once since I won't be eating that spent spinach. Naturally more cuke beetles show up later but I feel that I put a big dent in future generations.

Not to speak for him but I think rhizo is trying to make the point that Sevin kills in only 2 ways - direct contact with the bug (and the beetles are up on the leaves not at the base of the plant - only the larvae are there) or by ingestion (meaning they have to actually eat the sprayed leaves). The spray, once it dries has short term effectiveness as it is quickly broken down by the environment and that is what allows such quick post-spray harvest times.

From the Sevin FAQs: "Q: How does Sevin® control insects?

A: Sevin® has a dual mode of action. It works on contact and through ingestion. Sevin® is nonsystemic, which means it does not penetrate plant tissue. After controlling the targeted pest, Sevin® is easily broken down in the environment."

As explained on the label for best effectiveness against stripped cuke beetles you spray the bugs themselves and up on the leaves.

Sevin is a very controversial pesticide for many reasons and one should always expect objections to its use given the harm it is proven to do to beneficials if for no other reason and the safer alternatives available.

So while it is certainly an option available it should still be used with great care and used correctly as per label instructions.

Dave

The bugs were on the base of the plant, not up on the leaves. They appeared to favor feeding on the cotyledons. Sorry, but that is what was happening... I'm not sure if you are intending to tell me my experience is not correct, but that's what it seems like. When I went out an scouted they were all under the cotyledons or on the soil. (And for that matter, not sure if Sevin kills Larvae, but don't want them around either!)

And if they will die from ingestion of the dried spray, then it is not contact only.

As I said, I found no beneficials - only cucumber beetles, and a squash bug. The flowers were not ready. Considering Sevin breaks down rapidly in the environment, I would think that makes it a pretty safe option. I am not aware of any pesticides that kill cucumber beetles but not beneficials, or any that are completely harmless, but if there are I would love to know about it, and would happily use that instead. The one organic option I am aware of - pyrethrin - is neither of these things.

Not sure why you get so defensive. No one is telling you are not correct. Merely trying to clarify what you are saying - if not for your benefit then for other readers - and about how that particular product works best and how it is normally applied.

You readily admit in many of your posts to limited experience. So why is advice from those with much more experience offensive to you? You asked for tips and about other methods of controls. After 1 reply you decided what you were going to do and how. More people posted and you didn't like the questions or answers. Fine. But if you don't like what you get in replies it isn't any sort of personal attack on you, merely other people's opinions that differ from yours.

The Sevin FAQs I quoted above address your questions about how it kills, how it should be applied and where for best effectiveness. It is primarily a contact pesticide with some secondary ingestion benefits for a limited amount of time. Further all resources that recommend the use of pesticide sprays of any kind will always recommend that you focus on spraying the bugs themselves rather than the plants for the best effectiveness. That aspect of pest control is pretty common knowledge.

<Are row covers or hand pick the only options besides broad spectrum insecticides?>

No. However they are acknowledged as by far the most effective methods of control that do not also risk all the beneficials whether you may see them there or not.

Other controls include diluted Pyrethrum sprays, onion and soapy water sprays, diluted water + ammonia sprays, sticky traps, cultivating around the base of the plants, DE, Neem Oil, beneficial nematodes, lacewings, and spined soldier bugs. Then there is Kryocide, Admire, Sevin, etc. The choice is yours but when one asks about the use of any highly controversial pesticide you can guarantee you will get replies that will disagree with you. You need only pull up a few of the hundreds of discussions here about Sevin to see the truth of that.

Dave

Dave in your many replies to my posts, I get the feeling like you aren't even reading what I am saying (or rhizo for that matter), and just spouting off some generic answer.

The main reason I am getting defensive is for comments like this, "the beetles are up on the leaves not at the base of the plant - only the larvae are there", where you are in fact apparently denying what I am saying is true, or you are just not reading my post. Obviously that is going to make me defensive, when I just posted that I went and scouted and the beetles were at the base of the plant - and just kind of had an argument about it for that matter with someone else. If you aren't talking to me but just giving general advice that doesnt apply to me (in my topic) then by all means you should say so or I am goimg to assume you are talking to me. (By the way, some googling reveals that they are in fact commonly at the base of the plant early in the season.)

In my other seed starting thread you kept insisting I was saying the seedlings were too big for the pots and needed to go outside right now when that wasn't at all what I was saying. And you know what, I was right, the plants were rootbound by the time I planted them out - which was early. You are often unnecessarily argumentative. And you are backing up rhizo when you are actually contradicting him. I'm sorry, I am just trying to sort out a real answer - and rhizo is not correct - the spray does not become completely ineffective when it dries - it lasts for several days and if eaten by the insect it will kill it. I said I wasn't trying to have an argument - I was trying to get the accurate answer.

I do admit I very much so have limited experience, but I do have some, and if only the same ideas from people with 20+ years of gardening experience (especially so those with the biggest egos) are the ones that are allowed to be given, the knowledge base never grows, incorrect ideas never get challenged (and in this thread there are two), and this would be a pretty boring forum. One of the first things I learned was that what you read online is not always true - even sometimes from experts. I understand you are king of the hill here, and you don't like anyone challenging you, and honestly I think I am just going to bow out. Enjoy your forum.

I wanted to share for anyone reading in the future: the spraying was effective, I did not see any live cucumber beetles today. Considering that the Sevin has probably already broken down, I did not spray any beneficial insects, and my garden is still teeming with life, I would say I was successful in doing an effective treatment with minimal side-effects, despite dogmatics.

I would also add that perhaps others should do as Dave suggests and go read those other discussions on this site... they are not at all one-sided.

Good to know, Peter, thank you!

To prevent another outbreak what I have done is to take some tape (duct tape works good but any wide tape should do) wrap around the palm of my hand so the sticky side is out.

Then lift each leave to look for eggs on the backside. Press the tape on the eggs to remove them. This works for any critters you see while you are there. It works like fly paper.

Time consuming yet very effective, tho it has to be done for several days.

HTH

Yes I have been looking for eggs, I scouted thoroughly today (and looking for SVB - I have been spraying the stems with BT in hopes it will get them as they borrow in (which may be a waste of time IDK... I am ready to inject those vines if I see signs of them burrowing... alas it is about to rain AGAIN!) I did not find many eggs. Thanks for the tape idea, I tried to squish and they just fell off my fingers. I will definitely keep an eye out. I squished a whole bunch of flea beetles on the potatoes today, they were sluggish in the heat.