I bought a 2 lb pack of native wildflower seeds at Home Depot, and my preschooler and I hand scattered them on the electrical right of way behind our property one evening when rain was predicted overnight. It's our first time doing this, so I have no idea if it will work. But even if we only get a few flowers, it was a fun mother-daughter activity for $7, and we'll probably do it again annually any year that I think of it.
