This species is called amaranthus deflexus (due to its creeping / recumbent habit) and is actually a short lived perennial, surviving the winter through its rhizome.
This is quite unexpected, well... I've noticed this plant before, but due to its small seeds size, its scarce productivity and small size I never considered it really worth investigating. It's not even listed on pfaf.org.
This rhizome thing, however, is most interesting.
Would it be possible to cross it with other amaranths? If the resulting hybrid is able to grow a rhizome and be more productive, then it will be worth giving it a try!
For now, I've collected some seeds.. I read they are dormant, will sow them next year. If I manage to dig a small plant from a roadside, however, I'll be more than happy to try and overwinter it! :D
