Erika House wrote:Alfalfa. It's pretty fast growing, grows in clumps but can also get stalks of several feet long if left to its own devices, and as a bonus is also a favorite with ladybugs!
Will Whitt wrote:Sam,
I may be a bit biased, but I think some Russian Comfrey would be perfect. It's seeds are sterile, but will very easily propagate through root cuttings; you cannot dig it up once it is planted unless you want it to spread. That said, you can very quickly expand your comfrey; I originally bought five plants and within 5 years, have well over 50 plants and have sold probably 100+ and haven't been very aggressive on taking root cuttings!
The beautiful thing with comfrey is you can chop and drop 5+ times a season (at least here in zone 7 VA), its got great medicinal value, its a great weed/grass barrier, and bees LOVE the flowers.