Controlling Cucumber Beetle / Bacterial Wilt

[hunter]

The past two years, my cucurbits have had bacterial wilt thanks to cucumber beetles. This year I resorted to using Sevin spray, but it hasn't eradicated the problem.

Does anyone have any suggestions for:
a) Ridding myself of cuke beetles
b) battling bacterial wilt

[Ruth_10]

I hope someone has some good suggestions. I sure don't. One of my cucumber plantings is going down right this very minute. I'm very concerned about my cantaloupe as well.

[Tomaddict]

Cucumber beetles are my worst pest problem. I'm a (non-certified) organic gardener and have had limited success controlling them in the past. As for bacterial wilt, controlling the cucumber beetles is the key - if you can keep the beetles under control, you won't have the bacterial wilt problem with your cukes and melons. An alternative is to select cuke varieties that are resistant to bacterial wilt (we've had success with County Fair), but I don't think varieties of melon that are resistant have been developed.

My plan for this year is to go after them with a combination of organic controls - neem oil (active ingredient azadarachtin), then a few days later with a pyrethrin/canola oil mixture which is effective against beetle larvae. And repeat this regimen a week to 10 days later. I'm starting to see cucumber beetles, so it's probably time to get started, as soon as the frequent rains we've had this week are past. I've tried repeated applications of the pyrethrin/canola mixture in the past, with limited success. Lost my more susceptible melon varieties anyway.

I'll try to remember to report back later in the summer on how successful are the alternating neem/pyrethrin applications.

Here is a good resource for information about controls that have been studied and Integrated Pest management strategy: http://attra.ncat.org/attra-pub/cucumberbeetle.html . They report that carbaryl (Sevin) works best against cucumber beetles in combination with a feeding stimulant.

Good luck, and I'd like to hear other ideas and reports of what has worked or not worked for others struggling with these nasty little turds.

[outsiders71]

I've spotted a few cucumber beetles out on my cukes this year. So far no major damage. The only thing you can do against cucumber beetles is grow varieties that are more tolerant to them and bacterial wilt. There are a few predator bugs that will kill them, but that requires having a food plant to attract and keep them there.

[carolyn137]

There is another way to protect your cukes and melons.

Use fabric row cover. Leave it on until both male and female blossoms are showing and then take it off to allow for pollination.

From the time the striped or spotted cuke beetles inject the bacteria and/or viruses into the plants it takes about a month, maybe a bit more, before any symptoms show up. And in that month you'll have lots of cukes and your melons, depending on the variety, may be close to maturation.

Try it. It beats lots of other methods and I sure never had much luck with pyrethrins as a spray.

[DeanRIowa]

I read somewhere that planting a couple radishes around the plants deter cucumber beetles.

I trellis most of mine, so I am going to plant a couple of radishes around the hills. Can't hurt.

Dean

[hunter]

Thanks for all of the suggestions!

[fortyonenorth]

Cucumber beetles have decimated several of my melons. Interestingly, out of 25 plants, they've focused on two or three. I hand-picked for awhile then finally resorted to using Bonide 7 "Total Pest Control" - active ing. is Permethrin 13.3%. At the 2 Tbl./gal rate it seems to have taken care of the problem with no immediate visible effects on the plants.

[Mark0820]

I have had good results with Sevin. It is about the only product I have found that gives me a crop of cucumbers for the entire summer. With all of the rain we have had this year, it can be a challenge to keep the plants sprayed. Rain does seem to reduce its effectiveness.

Something I read in Mother Earth News is to buy some bright yellow buckets and fill them with water. Place the filled buckets next to the cucumber plants. Cucumber beetles are attracted to yellow (blossoms on the plant) so they will fly into the water and be doomed. I have never tried this so I don't know how effective it is. I'm not sure I would rely 100% on this method, but I personally have considered using it in addition to Sevin (to see if I can reduce the amount of Sevin I use).

[carolyn137]

I'll still go back to my post #5 here from last year about the row covers, and that after tryng this and that for quite a few years. Works well with melons as well.

The striped and spotted Cuke beetles can infect more than just the bacterial wilt stuff but without looking it up, which I'm not in the mood to do right now, ahem, transferring bacterial wilt is bad enough.

I would plant 5 seeds in one place, thin out to the best three. Go back after they started to run vines and see one vine had gone down, pull that one only to see another one go down.

Well, you all know what I'm talking about. It wasn't my idea about the row covers, I think it was a Cornell suggstion way back when I used to get their bulletins, and it works.

[Mark0820]

I didn't think about this before, but be sure the problem is the cucumber beetle. If you plant squash, you could also have a problem with squash bugs. The damage caused by a squash bug looks very similar to bacterial wilt, and squash bugs have the potential to destroy the plant much more quickly than cucumber beetles.

I experienced this about 4 years ago when I planted squash. I thought cucumber beetles were destroying my cucumber plants until I ran across an article by Ohio State Univ. about squash bugs. I looked at my cucumber plants, and sure enough there were several squash bugs on the plant. I am convinced they destroyed my plants because the cucumber plants died very quickly (early in the season).

If you don't plant squash, it is much less likely that squash bugs are the problem.

[rnewste]

Two relatively "mild" Insecticides you may want to evaluate are Take Down Garden Spray:



As well as Hi-Yield Indoor Outdoor Garden:



The later does claim to control Cucumber Beetles:



Both are rated up to "Day of Harvest" use.

Raybo

[tjg911]

i'm organic and CB are "turds", i agree with the poster that said that!

floating row covers will work for melons but if you trellis cukes as i do then FRC aren't an option. i grow county fair as they are BW resistant and i have yet to lose a plant. CF is a hybrid pickler but if you peel the skin it's a good slicer. i find the skin tough, maybe bitter.

edited to add - CF seeds are hard to find and expensive. i got them at park last time and i suggest if you go to them order them at least 6 months before you need them. it took 5 months for me to get them, luckily i placed the order in october!

tom

[bitterwort]

I took Carolyn's suggestion a few years ago when we'd just about given up on growing cucumbers. Our community garden is overrun with cucumber beetles (and other insect pests), use of insecticides is extremely restricted, and our favorite cucumber variety is highly attractive to the beetles. The vines would appear healthy until they were just about to bear fruit and then bacterial wilt would seem to take them down in a day.

After following Carolyn's suggestion of covering the vines with row cover until female flowers appear, we got a bumper crop from each trellised "hill" we planted for the next two years. Knock on wood for this year. After two years without fruits, that seems pretty good to us. Thanks again for the advice, Carolyn!

[Stepheninky]

I too have lost a few plants this is the first year they have been a real issue for me. Johnny's has a pheromone that you can add to the sticky traps that will draw them to it. (have not tried this yet)

What I have been doing is using Green Light Fruit Tree Spray Neem Oil, Pyrethrins, &
Piperonyl Butoxide are the active ingredients.
The Green Light works really well though once you notice the problem CWV it is usually too late. This spray works well and next year I will use it often and early. This year it seems every time I spray it rains and I work so its hard to keep on it quick enough. It is safe to use up to harvest as well.

Cucumber wilt virus is one of the viruses they carry as Carolyn mentioned they do carry others as well, off the top of my head another that they carry is Cucumber Mosaic Virus (CMV)

At first signs you should pull the effected plants. As it works down the plants it can get into the soil.

One way to test for it is to snip off an effected stem. Wait 10 - 15 mins and were you cut place your finger and the watery sap will be very sticky and as you pull your finger away will even make little strings.

Hope that helps.