I have lily of the valley in a flower bed, too, and it was really travelling into my hostas and other perennials. I got a large piece of tin, about 12 inches wide and as long as the area I wanted to contain and buried it so the top is just even with the soil. This keeps the lily of the valley from travelling. I don't think there's any kind of plant that would head it off. Now it still travels the other way and comes up between the patio blocks. It will find any little space to pop up when it gets a chance. The only other way to contain it is to keep at spading deep at the edge of the bed and not let it go any further than you want it to. I'm going to have to find some more pieces of tin to bury next to the patio and make sure I have all the roots and pieces of roots dug out from under the patio blocks. Even a small piece of root will eventually become a new lily of the valley plant.

Wow...I want to plant some this year...I'll make sure to keep it far away from anything else! lol

Wow...I want to plant some this year...I'll make sure to keep it far away from anything else! lol

Please do. If you have a neighbor you really despise, plant it along their property line. I once lived next door to a nice guy with a jerk girlfriend. She planted this noxious thing along the fence and it grew right into my garden. Nothing got rid of it since I couldn't do anything about the source on his property.

Finally he dumped her and I repeatedly round uped the stuff on his property (with his permission).

I just responded to another post about Bishops Weed and how to get rid of it. I planted Pachysandra aka japanese Spurge, and it eventually choked out Bishops Weed - Pachy spreads by underground runners, but the roots are so dense it's difficult for anything to grow through them once they're established.

My neighbor has Lily of the Valley that is working its way over to my property, and since I had success with the Pachy and the Bishops Weed, I'm going to plant Pachy along my property line to keep the Lily of the Valley from spreading my way.

Pachy is not invasive, does well for me in both full sun and full shade with ample watering and a yearly dose of fertilizer, it's an attractive evergreen groundcover with shallow roots and easily removed if you decide to replace it later on or if they grow outside of a designated area. Low maintenance. It is one of the very few plants that grow successfully under evergreens.

You can plant them closer together if you want full coverage sooner than later. Web says not good in full sun, but I had mine in blazing sun and they did fine as long as you give ample weekly waterings. Within 3 years you should have a full attractive bed of evergreen pachy.

Good luck!