I tried DE on my squash and canteloupes, and it didn't seem to make any difference at all. But maybe it doesn't work against flea beetles.

I have a hard time trying to "dust" it. No matter what I do, it goes down in little clumps rather than a fine dust. Maybe I should buy a sieve and dedicate it solely to that purpose.

Or a tea strainer.

I never had any luck with DE. I've seen slugs slime right over it. I never understood why it was recommended. For slugs, I have better luck with something like "Escargo" which is a bait with iron sulfate or something like that in it that makes the slugs stop eating. For caterpillars, I use BT which also makes them stop eating. Both are organic and work way better than DE.

I think the trick with DE is to layer a good amount around the base of the plant, as opposed to dusting it on the top side of the leaves.

To dust, use a fine mesh strainer. Diatomaceous earth is only moderately effective as a slug barrier.

Take the time to learn that there is not a "cure all" for every pest at every stage of it's life cycle. Some won't work if it's going to rain or if it gets wet (like diatomaceous earth). Some don't work well if it's too hot, etc.

Pest management is complex, if you want to learn, a good place to start is here:

Integrated Pest Management
This lecture is presented in two parts. Each part is 90-minutes in length. Recorded in Sacramento County in California's Sacramento Valley, this lecture is by Mary Louise Flint, Ph.D., Director, IPM Education and Publications, UC Statewide IPM Project and Extension Entomologist & Cooperative Extension Specialist.

Education:
B.S. Plant Science, University of California, Davis
Ph.D. Entomology, University of California, Berkeley

Appointment:
100% Cooperative Extension

Research Interests:
Integrated pest management of landscape, agricultural and garden pests; biological control of arthropod pests; alternatives to pesticides; adoption of alternative practices by practitioners; innovative delivery of pest management information.

Topics discussed in the Integrated Pest Management Lecture:

* IPM references and resources
* Preventing pest problems
* Natural common enemies
* Making less toxic pesticide choices
* Controlling aphids, scales, caterpillars, coddling moths, tree borers, snails and slugs, and lawn insects.

You can watch the programs now online:

Just make sure you have Real Player installed or download it free.

Integrated Pest Management Part1 90 minutes

Integrated Pest Management Part 2 90 minutes

You'll want to bookmark the following link to Professor Flint's Lab Research on:
Controlling Pests in Gardens and Landscapes: Vegetables and Melons

I promise you'll learn one or two things to put in your gardening bag of pest management arsenals.

;)

Man, this is crazy. DE has been 100% effective as a slug deterrent for me. It never occurred to me to apply DE directly to the leaves or, that it was effective on caterpillars. I always sprinkled it liberally around the base of my plants. In fact, I've written various posts here through the years about the effectiveness of DE. It always amazed me that gardeners would tolerate slugs when DE was so effective.

Then, I read a post where someone commented about DE killing worms. And because I'm wanting worms in my beds, I've not used it in a while.

But, once I applied it around my plants, we never saw any more damage due to slugs, ever.

Works on ants for me.

Ed

I've always used a dish or shallow can filled with beer buried in the soil. The slugs get in and drown. Probably happily :-)

You're right. I never thought about the worms. Dang! What kills flea beetles and leaves the worms alone?

Iron phosphate works on slugs. Sluggo and Safer Garden are two of the brands brands. One advantage is it doesn't wash away. It is an actual bait and I don't think worms will eat it.

You can not get the DE wet. If you get it wet, it will not work.

Sink a butter tub of beer into the ground and the slugs will crawl in and die.

Anything besides beer? I don't drink! LOL

You don't have to drink to buy the beer silly!

They sell beer in single bottles and cans. Get a cheap six pack. Then you have six opportunities to fill a small butter tub and catch slugs.

...and we won't say anything if you take a few sips yourself ;)

I just manually picked caterpillars from my broccoli leaves. After doing that a few times over the course of a couple weeks the caterpillars were gone and have not come back. I also threw mine out into the yard. If you are concerned about them crawling back then squish them or throw them in the garbage. One big batch I put on my tray feeder for the birds to enjoy. The butterflies are likely laying eggs directly on the plants, so DE around the base of the plant would not help.

gratefuled (or anyone),

I have a SERIOUS ant infestation in my backyard. I want to spot treat the really bad areas. I have 3 little boys that spend 90% of their time at home out there. Should I just sprinkle it over the mounds? Or should I just go ahead and do the whole yard?

No worries about too much moisture here. LOL Phoenix, is like a fricking oven this time of year!

seraki,

Try coffee grounds first, many GW members have had good luck keeping ants at bay with coffee grounds.