Killing the "neighbor's weeds" in your property won't solve the problem permanently...Why not consider cutting in a flower/shrub bed along the property line? This would prevent the "drifting" of weeds from their property to yours, and would help you maintain the organic environment you've created...

Best of luck

This is a totally frustrated vent. (This ended up so long I doubt anyone will read it all the way to the end so I'll post a response and question first!)
To the first post: was good to hear positive results about the corn gluten. I started the year with that and thought it was helping some but the Safe Lawns opinion was that it didn't work so I stopped.
Has anyone used the Gardens Alive IRON-X?

I have had both ends of the spectrum- out of control weeds (and fescue seed) and now out of control chemicals.
New neighbors who had never had a lawn moved in. They are uphill and 90% of the time upwind. I get all their gutter water and some of the french drain water where it comes out at the street.
My beautiful Bermuda lawn is totally organic. Normal hand weeding was time intense for about 6 weeks in the Spring and then a handful of weeds a couple a times a week for the rest of the season.

1st year-Neighbor used heavy weed killer to spot kill weeds and edged the lawn with it. Bare spots that washed out then filled with weeds. To combat bare spots, he over seeded the entire lawn with a fescue blend (several times because the seed was not sprouting in his yard-it was all washing down and sprouting in mine!) I was in the last semester of an intense full time social work graduate program and had been eager to get back to my beloved yard-work. Instead I spent 8-10 hours almost every day for over 2 months, hand weeding the fescue and other weeds out. About July, I finally had it manageable. Then with the first cooler weather around October, a whole fresh crop of grass began to sprout. I spent the winter weeding it out. I've never had to weed in the winter.

This year: Neighbor went 2-3 weeks between times he mowed letting thousands of weeds go to seed. Then he hired a landscaping service to chemically treat his lawn. That was early April and it still stinks (mid-June).
Each time the service came, I asked what was being applied because I have two little dogs who potty out there and because of my own exposure with all the weeding I am still doing. And because I had just paid $2,000 for 300' of cat fencing I had planned to put behind the house (where the water from the neighbor's yard goes on its way to the creek).
First time, the man said "Stonewall" & "Momentum" and that he "didn't use pesticides, he only used herbicides". Not very reassuring. (He needs to do a web search "EPA:what is a pesticide?") As a completely organic gardener, a web search left me nauseated and frustrated that the careful organic balance I had established was about to become history.

As I continued to hand weed, I stopped seeing the earthworms that would surface to get away from the old screwdriver I use to loosen weed roots. Instead, I started seeing them dead, first in the gutter and on the driveway and lately on top of the blades of grass.
I had a naturalized bed below one part of the neighbor's lawn-my native periwinkle is dying and I lost several native purple asters. The chemicals in the above products are exactly what is recommended to get rid of periwinkle. When I mentioned the Stonewall specifically to the same service man, he said "Oh, we don't use that anymore". Definitely, not very reassuring, actually more than a little scary.

After that conversation, the neighbor's wife came out and criticized me for talking to "their service" saying unless I was planning on hiring them she didn't see any reason for me to be speaking to them.
Then she dropped the latest bomb. They are going to have the entire lawn killed off, then the yard tilled and re-sodded with zoysia. When I expressed concern about what that would do to my lawn, she got really defensive and declared that they "weren't trying to destroy my yard".(I bit my tongue and didn't tell her what a great job they had been doing without even trying.) Then told me I needed to talk to her husband because she had "far more important things to do". Again, I bit my tongue and didn't tell her about the "far more important things I had to do" than pull up their weeds and grass seedlings or stand with the hose washing their chemicals out of my flowerbeds (the lawn service's suggestion for my dying plants).

The Homeowner's Association says it is "soft-scaping" vs hard landscape changes so they don't need approval.
I had planned to do what another comment suggested-put in a raised berm for a crape myrtle bed and am still waiting for the approval of the architectural review board.

So, my neighbor's wife did not get the thrilled response she expected when she also told me they were thinking about putting in a mimosa or a magnolia tree ("you know those really big trees with the huge white flowers")in the little space left between my beautiful weeping willow and their ornamental cherry. There would go the sunlight for my crape myrtles, and, oh boy, I might get to pull out mimosa seedlings along with the cherry seedlings and the weeds that will be sprouting from this year's massive weed crop.

Her talk of their plans is really baffling since they have had a "for sale" sign in their yard for over a year.

I've begun to wonder if maybe I need one, too.

I feel for you guys. My neighbors are the "Zero-scape" sorts... Dead lawns, only mow occasionally, etc... and as you know -- it breeds lots and lots of weeds. We have *Large* mulch beds between properties -- like 20' of mulch... and this goes a long way towards keeping weeds and drainage problems under control.

I think a tastefully done raised bed planter with rail-road tie or layers of rocks for the edging would go a long way to both look nice, and to correct some of the drainage and weed problems....

As for aggravating neighbors -- They are everywhere... Not much you can do...

Best of luck

John

How were the results of Scotts brutal?