I'm trying to fight runners from neighbors' St Augustine coming
through my fence and taking over my Zoysia, and thought I'd
solicit the group for advice/tips.

I'm considering lining the base of my fence with a metal or
plastic strip that will provide a physical barrier to neighboring
grasses. My only hesitation is in wondering if that will
restrict water flow (both in and out) during heavy rains, causing
excessive puddling.

Does anyone know if there's a soil nutrient balance that favors
zoysia over st augustine? How about other factors, such as
letting it bake in the summer without water, or mowing it very
low (zoysia likes being cut lower than StA, doesn't it?)?

What have some of you guys done for this situation?

Thanks
-Dave