[vash]

i am slowly re-doing my front lawn. grass is out. i let it all die. i have been round up-ing what is left, and i have removed all of my shrubs. it is essentially a blank slate. i just reserved my lawn tiller. i am going to set it shallow and skim off my dead lawn. then run my simple main water lines off my existing sprinkler solenoids. shallow.

here is my question: i am going to build elevation changes..small hills. three small hills with drought resistant plants. in between the hills, decomposed granite. i'll keep it all separated with that bendable landscape border.

wont my border material overturn with just topsoil on one side? i imagine staking out my borders, wheel barreling in my topsoil, running my irrigation around, covering it all with landscape cardboard, planting, mulching and then bringing in the decomposed granite and tamping it down. can the border hold up the topsoil in the meantime? (like a mini retaining wall?)

i dont want to cross contaminate topsoil over the tidy gravel.