Jun 30, 2009 -- 8:08PM, Wendy Burbrink wrote:

• Hi, I just joined and I have a flower garden of all dahlias.  This is my first year to put them all together, but it makes one nice place for the earwigs. I MUST find something to GET  RID OF THEM. HELP !! I know I can do insecticidal soap spray, but that would take me hours, wouldn't it and when I water overhead, since I do not have drop system, it will wash it off, Is there a chemical I can buy or anything and what do you find is best.  I am calling the Earwig War and they are winning !!!!!! Wendy
• and how do I change to larger font ???
  

Hi, Wendy. Seems you've two problems! The first is the font. When I responded with a quote of your posting, I noticed you had both the superscript and subscript buttons on, which is what made your font so tiny! Next time make sure you don't have a light blue highlight on neither the X₂ nor X² buttons that are to the left of the Omega symbol in the text box's format area.

Now for the earwigs. I hope you want to avoid the chemical "bomb" in your war against them at all costs. So, there's two things you can first try:

1.  Earwigs love moisture. Do you have a thick organic mulch of some kind dressing the soil in your dahlia garden? Or, are the dahlias planted so closely that the soil is shady and moist under the foliage?  You mention you water overhead--are you SURE you are not overwatering and so the leaves and soil surface remains too moist all the time?    The thing to do is remove (or at least drastically thin) the layer of mulch from the dahlia bed. Earwigs feed at night (in darkness) and then run for cover under the dark and moist mulch in the daytime. Remove that and you likely deter earwigs as well as dry out their eggs.  Or, if there is no mulch but foliage is think, you need to increase the air and sunlight that reaches the soil in-between your dahlia hills to create an environment that is drier on the soil surface.
2. In addition to #1, also put out some cheap newspaper traps. Since the earwigs love dark and moist, dampen and roll up some sections of an old newspaper and set them on the soil throughout your dahlia beds in the evening. As the sun comes up the next day, the earwigs will scramble to the moist, dark roll of papers. You then come by about 7 or 8 am to collect the papers and dispose of them in a plastic bag (and removing the adult earwigs).

If you find these organic methods are making you think of waving the white flag, there is the chemical solution. It's stinky, but could be ultimately effective. You'll need to look for a product like Orthene. I used this for pests on tropical hibiscus, and it no longer is marketed as Isotox, but something else at the big box stores. I think it's someting like "Pt  Systemic Insecticide". Look for it in a dark green plastic bottle with yellow label (From Ortho) or white bottle with red and purple label (from Bonide) and look for the tiny words that state "Active Ingredient: Acephate __%".

Acephate is smelly when wet and should be spray onto the soil around your dahlias in the early evening just before the earwigs come out and about. Follow the label directions for certain, since acephate does have health concerns if you deliberately breathe in the water and acephate spray or get it on your bare skin. Also make sure no pet animals will be walking/snorting through the dahlia bed while the spray is wet for several hours overnight.

Another reality of the use of acephate is that it will kill all insects around the dahlias, including the beneficials like ladybugs.

You really just want to reduce the numbers of earwigs to a tolerable level. Some earwigs are good since they eat aphids, but earwigs do have a palate for dahlias.

Good luck in your attack, hopefully the two non-chemical operations will be successful.

Another option would be to remove the carpet and lay down a THIN layer of mulch (say, one inch) and also use a pre-emergent herbicide (granules). The pre-emergent will only affect germinating seeds, and not harm the dahlias or other plants already growing.

That carpet is extremely thick and moisture retaining. Even a thin natural mulch like dried grass clippings or pine bark will be considerable more porous and dry more quickly than the carpet.