I suspect the best way to grow white asters, Spanish needles, or Alabama’s former state flower, the regal golden rod, is to mow, bush hog, or disk fallow areas each and every year (or two) after the first frost. You want to maintain fallow crop lands, field edges, and ROWs and above all don’t let them get chocked out with sage grass, honey suckle (which is an oxymoron) briars, or small trees and brush. The herbicide Grazeon is taking over from 2-4-D and Round Up. Grazon only kills broad leafs, is deadly on clovers, and is used on pastures, ROWs, green spaces, walking trails etc. I am told (but you better find out for yourself) that Grazon can be used on pastures while cows and horses still graze. Since Grazon is usually applied early in the year, and by a contractor, if the contractor finds a ROW, trail, or green space that dosn't need spraying right now, they just may shrug their shoulders and decide to save the fuel, time, and Grazon needed to spray it.
Remember, you bee living in the South, and every square inch of dirt exposed to the Sun will year after year naturally grow out something considered a weed by everybody but a beekeeper. If you can keep the Sun shining on that fallow crop land, field edge, hunting lease, or ROW you and your bees going to find asters, golden rod, and Spanish needles growing on it in no time at all. I am not saying that you can’t plant an aster, but I am saying that it is much easier to keep what you already have, instead of trying to kick Mother Nature in the seat of the pants by planting weeds. By now the old girl’s got weed raising down pat.