I ordered Dry-Climate Browsing Mix from turtle supply but I have a few questions.. I am looking for plants, bushes, grasses that will not spread since I grow them in a raised garden cut off from the yard. I know many grasses/weeds spread just by wind taking the spores even if they're 50' away, but most "bushes" I've ever seen don't spread even though a seed here or there will get in the grass just like any other plant. I just dont want something I plant spreading like a wildfire in my main "grass" that has taken a lot of effort to perfect and get weed free.