and yes I know they are poisonous

I don't think so. My sister grows many different brugmansia plants and she has as many JBs as I do. And believe me I have a lot.
Olga

The last two years I've had Angel Trumpets growing in my yard and have noticed no reduction in the numbers of Japanese beetles.

Poke Salet reduces the numbers. They like poke better than roses. They adore crape myrtles so once they are through ingesting them, they will turn to your roses. ;-)

I didn't think so... oh well I had to hope. I saw my first JB yesterday. UGh!

In Pat Lanza's book (Lasagna Gardening) she suggests planting wild grapes somewhere away from your prize plants for the Japanese Beetles to eat. SHe says the JBs love grape leaves. Has anyone tried this?

Haven't tried it, but I was at a friend's house a couple of years ago, and the JBs had totally taken over a grape vine in their backyard. And a member of our rose society also reports that they love her grape vines, totally skeletonize the leaves.

Sunnishine, I doubt you saw a JB yesterday. They are a July/August surprise. They are still grubbing right now.

Grape vines aren't a dependable JB magnet. My wild grapes out in the woods and my muscadines and Concords aren't terribly bothered by JBs.

In my garden in east TN east of Knoxville, June 6 is the date for first appearance of the voraceous hords. One year I saw one the second week of May, but she didn't live long enough to prosper.

actually beetles show up here in June and are gone by mid july. It has been abnormally warm lately. It was in the 90's all weekend. It unfortunately was a JB. I see a lot of them and know the difference between them and imitators. He was munching away on a rose and was promptly drowned then smushed.

I agree he was abnormally early even for here...but he was eating away nonetheless.

I had two huge walls of purple wisteria growing around the swimming pool, which I found to my dismay that the JBs adored. It did not, however, deter them from munching on the roses and clematis. They dined on all.

I even bought gallons of 'Bye-Bye Beetles' in my vain attempt to drive them off; they took baths in it where little pools of white cedar-smelling residue remained on the leaves and then flew away; only to return later to munch some more.

I've come to the sad acceptance that nothing I plant will deter these devils from arriving in June and not departing until October. I just wish I could keep ducks and guinea hens where I live.
-terry

I will add that introducing brugmansia as a remedy for a JB problem, might just introduce another problem: a brugmansia problem. In my area, brugmansia self-seeds with vigor, popping up in driveway cracks, foundation cracks and everywhere else in the garden, too. I finally rid my property of them after much work. I wouldn't bring brugmansia in even if it did solve the JB problem. That's just my experience.

I myself have to fight with those nasty japanese beetles. There are a few way to fight with those nasty beetle. It only reduce the number of beetle from 10 to 1. Well in spring make sure you put those pesticide granule. The Japanese beetle live underground as a grub eatting away at the root your plant. Make sure those granule are made to kill grub. Also if you have a flower bed that the JB love to eat, try planting some lemon grass in it. If you don't have any lemon grass try garlic. The most important time to fight those Japanese beetle is in the summer. Buy a Japanese beetle trap and set them as far away from your plant as possible. Then buy (usually I grow them) some really hot pepper and put it in the blender and then liquify them. Filter it with a old sock or somethings so you can spray them on your plant. This way when those JB bit into the leaf it will not taste right. It also work as a barrier for other insect that eat the leaf. For extra protection buy a bird house. Those bird that live in them love Japanese beetle.

The hot pepper come in a wax form. You can buy it online or just make your own. Just remember to apply it after every rain. It don't burn your leaf or make the fruit fall off. So you can relax......