I really don't know a lot about all the different chemicals used on gardens. I'm wondering if that won't also kill beneficial insects?

Yes, and Google reveals it is also highly toxic to earthworms. I am no expert on pest eradication but I doubt anyone on this site would recommend such an approach.

It would be interesting to understand what exactly you're trying to kill. I believe that malathion has a half-life of a few weeks, and it's mainly a surface insecticide. As such, I'm guessing it will affect mainly flying insects. At least for mosquitoes, it doesn't work on larvae. Of course, many of the flying pests won't hatch until after your malathion is long gone so ....

Malathion is extremely toxic to bees. As such, at least for pest management in fruit, the application is done after flowering.

Bottom line:

Using it in that manner won't accomplish what you want.

Another bottom line:An interested gardener, who periodically monitors his/her garden, is the most effective pest management.

It might also be cause for thought to know that Malathion has not been sold in the UK for home gardeners since 2002. Since you mention looking for organic solutions post germination contemplating using Malathion doesn't compute.

As well as vigilance, shallow surface cultivation with a rake or hoe can help eradicate pests. Eggs and larvae are exposed to birds and the elements. You can do this even if you are no till because you are only stirring the top inch or so.

Most pests in home gardens are easily dealt with when they appear. Without poison.

SVBs aren't easily dealt with when they appear. Nothing is easy with SVBs. Not that I'd use malathion on them, but still.

I tried every organic method and every single day went out to hand kill bugs at least twice a day in the entire garden. I also occasionally used seven dust.

Mike bug problem got worse every day. There's absolutely no way anyone could've kept the cucumber beetles out of my garden without working more than eight hours a day seven days a week. Bacterial wilt ravaged my melons cucumbers and squash.

I do not want to kill bees or beneficial insects but the bottom line is there's no way I'm gonna be able to stop them this year without using harmful chemicals.

Don, if raising a garden organically is important to you, there are ways. However, it is true that it requires dedication by the gardener. It often comes down to priorities and if you can make time.

Just as an example...

I'll be growing a cucumber this year. I'm not super into cucumbers, so I've never bothered before. Two things that are important to me are: growing organically, and saving seeds.

To save the seeds, I decided on an heirloom. If I decide to defeat the bugs, I'll use row covers. What I'll have to decide is... do I want to spend the time hand pollinating if I put them under cover? Another option is to plant more than I need and just know that the bugs and disease will get them eventually. That idea is called tolerance. It's knowing the pit falls, and planning accordingly.

Now, I'm not saying you have to go organic, rather it's your personal measure of tolerance. Since I know the bugs will shorten the life of the plants, if I choose to, I could do a succession planting. A few weeks to a month after the first crop, I could start new seeds, put them under cover, then as the first crop gets hit with bugs, the second crop is maturing. By the time the 1st is waning, it's time to remove the covers from the second for insect pollination.

I'll grow more plants than I need knowing the bugs will get a percentage of the crop. I'm sure that with cucumbers, in my climate, I could do a 3rd succession if I chose.

If you don't have the time, and organic isn't that important, then you can make other choices. I'm just saying that there are ways, and since I'm not very experienced with cucumbers there might be other ways I haven't yet learned to deal with the problems.

As another example, I know there are parthenocarpic varieties that can be grown under cover hidden from the pests, and which don't require either insects or hand pollination to bear fruit.

Edit: I did grow my summer and winter heirloom squashes under row covers last year, hand pollinated, and they did fine. There were no bug problems (I was especially happy that the squash vine borer was defeated... it is terrible here,) but they both got powdery mildew. However, I still got all the fruit I could use and more.

I don't have experience with them explicitly, but what I see on the web is that malathion may be only "marginally effective" against cucumber beetles. And be careful. Malathion combined with carbaryl is phytotoxic to plants (as in, they'll stop the plants from growing).

I'm still a little puzzled why you would apply malathion weeks before the last frost. There won't be any cucumber beetles around then, and the malathion won't last until there are. It's a contact insecticide, and the larvae are mostly shielded underground. Larvae most likely aren't just developing in your beds, in any case. That is, if it works, it's going to work directly on the beetles.

As noted by several responders Malathion is a contact pesticide. it has to come into direct contact with the beetles. So how is using it ahead of time going to have any effect?

The are a number organic beetle controls available - Surround (kaolin clay) one of the most common, diatomaceous earth another - if organics is preferred.

Dave

I wouldn't even bother to garden if I had to use pesticides. The main reason I garden is to be able to eat pesticide free veggies. I would suggest you look into trap crops and plants to grow that attract beneficial insects.

I can honestly say that if you used every organic method available and spent 10 minutes per day pet cuc plants twice a day 7 days a week you would not have got a cucs from my garden. I planted plants every 1-2 weeks all summer. I was out there every morning while they were slow, to many burried inside my huge squash plants - to many places to hide. 2 hours a day 7 days a week would not have been near enough.

"Used every organic method available."

Wow that is quite a claim! How is it that organic gardening can work for so many? There must be some other explanation for such total failure of a crop. Are you sure there were no other factors, pests or disease issues going on that were just coincidental to the cuke beetles appearance?

Dave

Are your cucumber beetles striped or spotted? It is said that the former just eat cukes. The latter eat many things. If you have the former, it may just be wise to stand down from cuke cultivation for a few years (unless you have a farm near you that's growing loads of cukes).

Kaolin clay and DE are worth trying, but don't just spread it on the ground. The beetles don't spend a lot of time crawling on the ground. Best to dust the plants with it. With DE at least, you do that by misting the plants, and then blowing the stuff into a cloud around them. Of course, you have to redo it after it rains. I've had a lot of success with DE and leaf-footed bugs, and I hear it works with cucumber beetles if you do it right. Now, it isn't completely clear what DE does to bees, but I suspect it isn't good. I'd just avoid application when the flowers are in full bloom.

I had plenty of striped cuke beetles on my squashes last year.

At the beginning of the season they were congregating and mating at the base of the plant, under the cotyledons, so I did carefully and locally spray the base of my seedlings with Sevin, and it was very effective for a little while, though many disagree with the use of this pesticide in any situation, I found that this was a completely reasonable use - localized, thought through, unlikely to have much deleterious effect (no bees present and no fruit even forming yet), and much different than prematurely spraying your entire plot.

Yes. Good point. My mistake. The host plants of striped cucumber beetles are cucurbita, and that includes squash. So I'd amend that to say that if you have striped beetles, you might want to stand down on raising cucurbita. If you have spotted beetles, on the other hand, they could be coming from anywhere.

Are there varieties of cucumbers that are at least somewhat resistant to bacterial wilt? Perhaps that may give you more mileage.

We get the striped cucumber beetles here but I have seen them on many things, not just cukes but they have never been the problem for me that grasshoppers are.

All the references I can find say that the striped cucumber beetles attack cucurbitae only. That is, cucumbers, squash, pumpkin, gourds. If you see them attacking other things, they might be corn rootworms, which attack a bunch of different things, and look similar. I think the OP noted in a parallel thread that there was a cucumber variety that was resistant to bacterial wilt.

I've been using "Surround" for a few years now with very happy results. But I also wonder about Don's soil's ability to grow vigorous plants. Is the soil being fostered on an ongoing basis? Are the plants nutritionally supported?

Don, the more a gardener relies on those strong broad spectrum pesticides, the more he/she will be forced to use them. Their use has proved to cause a resultant population explosion of more pests.