Organic wasp control for vegetable garden

Several years ago we converted our vegetable garden to raised beds using concrete blocks for the walls of the beds. This year we find that wasps have made their nests in some of the cavities in the blocks and we have been stung several times now while picking vegetables or watering the garden. After the season is over we can fill some of the holes, but now we need to find some kind of spray to kill the wasps so we can harvest our food. Short of buying a beekeepers outfit which is expensive and cumbersome for gardening, does anyone know of an organic wasp control? Any help will be appreciated.

I believe a direct shot of pyrethrin/rotenone or just pyrethrins should kill them, if you do it at night. Anyone?

Zeppy - Wow. What a quick response. This is my first day on DG and already I have received a suggestion. Our 30 x 30 garden has a fence with hardware cloth that is buried 2 feet for chipmunks and voles (voles were already inside and still a problem), covered with netting for birds, high enough to keep deer out, and now we can not even harvest our blueberries or vegetables because of the wasps. The local Cornell Extension agent just suggested a mint and clove spray so I have been boiling a lot of mint and cloves for two hours. We do have some rotenone. Do you see any harm in mixing some rotenone in with the mint mixture??

Have you tried a wasp trap, hanging it some distance away from the garden?

I hope this is an appropriate suggestion to make -- when I had a raised bed with cinder blocks, I filled the holes with soil and planted moss roses (portulaca). I was afraid the heat would kill them, but they loved it. No room for wasps.

mygardens, I have wasps too. They come out every year at this time. I'll be watching this thread because we've had really bad encounters in the past. I got stung in between my toes last year & thought my whole leg would fall off. Real PAIN. They were in a big pot of impatiens & DH gave them a good shot with wasp spray. Killed the wasps....also killed the plant. Tried a wasp trap but only attracted what seemed like every wasp for miles around.

Someone said they build nests underground. Our local greenmarket sets out bottle traps amoung the fruit (outside) with sugar water in the bottles. The wasps get trapped in the bottles & customers avoid getting stung. One year they set up house in a city fire hydrant. Had to call the fire dep't who then called animal control (I kid you not). I too would like to use organic if I could only pinpoint the nest(s). Thanks, Gloria

Love the suggestion about planting portulaca or maybe a variety of plants. However, the top layer of our blocks are sideways so the holes are horizontal and I am afraid that the soil would wash out. gloriabythelake - some wasps do build nests in the ground, but not this kind. Two of us got stung. They really attacked us and we have had to resort to a makeshift bee outfit to weed/harvest our crops. We have tried a number of organic methods. None have worked. Unless we find something soon, I am afraid that we will resort to patching the holes with cement after the growing season is over or perhaps in the spring before the next season starts. Quite a job since we have many raised beds and bays in the garden area, but we can't grow food with this problem.

Probably the problem might have been avoided if we had used something other than concrete blocks, but we did not want to introduce any kind of chemically treated wood in the vegetable garden and the research we did indicated that other wood might attract unwanted insects and would decompose too quickly. Concrete seemd to be he best material for the food crops, but the wasp problem has been frustrating.

my gardens, have you considered stuffing those concrete block openings with some chicken wire (or similar) and pressed moss hanging basket liners, filling them with soil and then planting alpine strawberries, prostrate rosemary or thyme in them?

Here are some links showing the the liners to which I'm referring.

http://www.gardenartisans.com/liners.html
http://www.bestnest.com/bestnest/RTProduct.asp?SKU=GAR-R584


Of course, if you are a fellow knitter, you may want to knit your own out of garden twine:
http://www.diynetwork.com/diy/na_knitting/article/0,2025,DIY_14141_3072978,00.html

Raid has a product I've seen called Earth Options, I think it has something like cloves for an active. It's probably not totally organic, but may not be as hard on your plants as the regular wasp spray.

garden_mermaid - all great ideas but the garden is too big and it would be too expensive and time consuming for so many blocks......However - I think if we do the concrete thing or whatever we do, we can do your idea on some of the blocks and it would look great. Thanks for the links.

Victor (Safer) has a "poison-free wasp & hornet spray".

http://www.groworganic.com/item_PBT435_VictorsupsmallregsmallsupPoisonF.html

It looks like a mixture of mint oil and sodium lauryl sulfate, which is a detergent. You might have some detergent/soap around the house that you could mix up with some mint and try that.

ecrane3 - Our local Cornell Extension suggested a solution made from cloves and mint. I boiled a heavy concentration of the mixture and sprayed it in the holes. It did not seem to have any effect on the wasps except they were very angry the next day. Someone recently suggested using a solution of Elmer's glue and spraying that in at night. The idea is that when the glue dries they won't be able to fly. Somehow, as much as we want to get rid of the wasps, a slow death is uncomfortable for us to think about although we may get desperate enough to try it.

As for the Earth Options, I really would not trust any Raid product on my vegetable garden. Anything we put in the blocks will leach back into the garden. I did a quick search and what I found did justify my concern. Here is one simple article: http://www.dld123.com/q&a/qandatemp.php?id=Q44

Back to the drawing board.

Too bad Raid's trying to be deceptive about their product--personally I was skeptical too, figured there had to be something nasty in there! But since I haven't had any need for sprays like that I never researched it.

I'm wondering if there might not be a better way to make your mint/clove solution--did you just boil it in water, or was there other stuff in the mixture too? The things that are going to kill the bugs are clove oil and mint oil, and oil isn't soluble in water, so if all you did was boil the mint and cloves in water then you wouldn't have gotten much if any of the oils into your solution. If you add a bit of dish soap or something that might help (maybe not though--I'm not sure how hard it is to extract the oils out), or if you can find a source for clove and mint oil themselves that would undoubtedly be the best option.

It's really maddening when chemical companies will add a natural ingredient to a chemical product and try to pass the whole product off as natural. And the marketing strategies of laundry detergent, etc., being good -- because it smells like summer rain or the mountains. I have to wonder how stupid they think I am. Can't you hear them laughing? I'm in danger of going off on a rampage here so I'll stop. This is for gardening.

mygardens, I'm assuming you cemented the cinder blocks in and can't turn them, so stuffing them with something or other would be the only solution. What if you used mermaid's suggestion (which I loved, of course) on some, cement some, and set wasp traps in some? You want something that doesn't take a lot of maintenance, of course. It would be nice to come up with something that would be productive as well as effective. If my little brain comes up with something, I'll let you know.

Can you post a picture? One of us might go oooh oooh oooh and know just exactly what to do.

Thanks all - I am really getting some good suggestions. ecrane3 - yes, I boiled a lot of mint and cloves for about 2 hours but I guess this is not the same as extracting the oil. Maybe just buying commercial mint oil and clove oil will be better. It should not be that expensive and a whole lot cheaper than some commercially labeled product. Or maybe I will first try to add some detergent to my current mixture as mermaid suggested. I wonder if a very few drops of dormant oil might also work with the clove/mint solution????

brigidlily - the blocks are not cemented in. Good idea. I will take a photo today. Only the top layer is not below the level of the dirt.

brigidlily - Here is the photo. The garden is about 30 x 30 with 4 foot bays for vegetables and 2 foot bays for blueberries. It is completely fenced for chipmunks, rabbits etc, and covered for birds. After we resolved those problems we discovered voles and then the wasps so those are the current problems we need to solve before next year.

I saw a review in the NYTimes about a new book that sounds all too familiar. It is called "The $64 tomato - How One Man Nearly Lost His Sanity, Spent a Fortune, and Endured an Existential Crisis in the Quest for the Perfect Garden" ( http://www.64dollartomato.com/ ) . We are not exactly looking for the perfect garden. We just want to harvest something before the wild things devour everything. We have spent so much already that I am not sure I want to invest in this book, but it sounds like good reading. Maybe I'll see if I can get it in the library!

Anyway, you can see how the blocks are laid. There are holes both inside and outside the planting bays.

So, they're not proportioned so that you could just flip them over so the holes go down instead of across. So planting in them like I did is out, unless you bought more to keep the width right. Hmmmmm... I wonder if just stuffing them with something like coco fiber would work. I mean, what a pain to go with concrete. That would be labor intensive.

I'll keep thinking.

The book sounds too scary. I don't wanna know!!! :}

I have wasps, too. I've been stung a few times, but I try just to stay out of their way. We have almost no bees any more to do the pollinizing, so I regard them as belligerant assistants. Yuska

mygardens, very lovely garden indeed!

My DH asked my to let you know that those types of concrete blocks are weakest when laid on their side as you've done for the top layer. They will be more prone to cracking when laid like that (actually he said that karate chops demos with bricks love to use these things when laid sideways because they are easy to break).
The holes do seem a bit two small for planting in. It looks like you'll need to fill them in with something, then seal off the opening. My concern with filling without sealing is that some other critter or insect would take up residence in the filling.

garden_mermaid - since these walls are not meant for construction or weight-bearing purposes, I don't think that one block on top will be a problem. Laying one block in the conventional position and a smaller block sideways gave us a total depth of 12 inches which is all we needed. We cultivated a few inches below the first block before adding the 12 inches of soil/compost and that gave us a deep enough bed.

brigidlily - stuffing each block with coco fiber seems like a lot more work than concrete. The interior of the block does not need to be filled. I think that a once-over with a trowel of concrete will seal the holes. Every method will take time for this size garden, but so far, concrete sounds as if it might be the best in time and money although I do like the idea of leaving some holes for strawberries etc. and I will probably try the mint/clove oil before resorting to the concrete.

I saw a mint oil wasp spray at the hardware store today, would have wrote the name down but I didn't have paper with me and now I've forgot it--sorry! I'd never seen it before so don't expect it's widely available anyway. But I noticed the ingredients were 8% mint oil and 1% sodium lauryl sulfate if that helps you with your recipe. There was a product with 4% mint oil too for normal bugs, but the wasp one had 8%. The sodium lauryl sulfate probably helps kill a little, but mostly I think it's in there just to make sure the mint oil dissolves, you could probably use dish soap instead.

Great - Those details make my effort a bit more focused.

I have wasps, too--even one by my front door--and it's a wonder I haven't been stung. I'm afraid of wasps and bees and allergic to almost every bug out there, so it's a real concern. There's an area that I want to clear for raised beds, but the previous owners left a debris pile of sticks and branches in the middle of it. Then weeds grew up through it. I've seen a ton of wasps over there, so I'm betting I have a nest.

So I would also like to know how to get rid of the wasps without getting stung, so I can set up my raised beds. I wanted to set them up this fall so they'd be ready to go in early spring when I plant, but maybe I'll have to wait until the ground, and the wasps, are frozen before I can do anything.

The exterminator took care of the wasps by the front door. I may ask him about the debris pile when he comes back out. And no they don't use Instant Death poison. They use slower-acting, bio-friendly products. One of the reasons why I called them instead of a standard exterminator like Orkin.

You may prefer to have your wasps all minty fresh and use the mint oil spray, but I have always used windex (or the off-brand ammonia based windex lookalike). It WILL kill a wasp or other insect just like hotshot. I used to spray wood roaches (they fly around like helicopters from hell) when I lived in NOLA.

I doubt the windex would be very effective on a nest, however. You need something that immediately effects the nervous system of insects (i.e. not birds, mammals, reptiles) like a pyrethrin to hit the nest. Unless you enjoy running for your lives. To each his/her own.