All the experts say that millipedes aren't a problem.
Try looking up millipedes on the internet and you'll see lots of pages that say "Millipedes generally aren't a problem in the garden," blah, blah, blah. They usually add that millipedes like decaying organic matter and rarely bother plants.
Hmmpf! I beg to differ. Does this look like a problem to you?
My raised beds are almost completely full of nice, fluffy, moist compost (organic matter). They used to be mulched with grass clippings (organic matter). I eventually had to remove the mulch on the vegetable beds because it was causing such a population explosion. There are thousands of millipedes in each one of my vegetable beds. They are in organic-matter heaven.
How about this? Does that look like a problem to you?
There are three different kinds of millipedes in these beds. I don't even try to catch the little ones unless there is a pile of them where I can scoop up a bunch at one time.
Not only do they eat the organic matter, but they also eat the roots and leaves of some plants. I think they eat the seeds I plant as well. They also leave big tunnels throughout the soil which causes it to dry out and damage the roots of the plants. We see millipedes in other areas of the garden, but not to the extent that we see them in the raised beds. See the millipedes on the plants? What are they doing up there if they aren't eating the plant?
My method of eradication (which isn't working) is to hand pick these little devils and dump them in a bucket of soapy water. It definitely kills them, but there is no end to them in sight.
The best time to catch them is early in the morning when they are on the surface of the soil hiding under the leaves of the plants. Another good time is right after it rains. Since they have to breathe, they climb to the surface after a heavy rain to avoid drowning. Sometimes I flood a bed with tons of water to get them to come to the surface where I can catch them. Regardless, these beds still have a million millipedes.
One morning, I counted. I picked up up 150 millipedes out of only one 4' by 4' raised bed (1.20 x 1.20 m.). And that's just the number that I caught. They move pretty fast and burrow back into the soil as soil as they catch on to what I'm up to. I call 150 a problem. Even more depressing is that there were that many again the next day.
How about this one? Clear evidence that they do so eat plants!
Once when I was cutting some eggplants off the plants, a big millipede brazenly walked right in front of me. Since I happened to have my hands full, I reached over with the plant clippers and cut it in half. Do you know that it just kept on walking?! So, I cut it in half again. Even with only one quarter of its body, it didn't even slow down. So, I cut it again, and I'll be darned if the head and a couple of remaining legs didn't just keep on going. I was impressed with its will to live but I stomped on the head and killed it anyway.
The Bug Guide says that millipedes can live up to 7 years. Oh, no! Tell me it isn't true. The Bug Guide also says that "any millipedes with bright color patterns secrete a compound containing cyanide" and they include a picture of my most populous millipede as an example. They do have a foul odor − not an animal odor, but more like a chemical odor.
Based on that, I don't think my next plan − getting some chickens − will work. I certainly don't want to kill my chickens with poisonous insects. I wonder if chickens are smart enough to know what they can't eat or if I'm going to have to protect my chickens from the millipedes.
Any helpful ideas, anyone?