Why not. Basically all they need is water and light.

Yes, I've done this successfully, too. I just added a drop or two of a balanced liquid fertilizer (I think I used schultz?) and occasionally I even sprinkled in some fish food and that seemed fine. They actually did better that way than in the tank! I had sword plants, a grassy valisnera (sp?), a ribbony plant, and a dwarf grassy thing. I actually saved my anacharis and did this too, and I felt like a farmer! I gave huge amts to a friend for his turtle to play in and munch on! :)

good luck!

That sounds like a cool idea! What kind of jar are you using?

I have a lot of interesting-shaped clear glass jars- some are just weird mason jars and others have those clamp down lids. I went ahead and made a small jar the first day i posted- hairgrass looks fine, but doesn't seem to be doing any better. Also put some hair algae in a jar to see how fast it would grow. I already have too many plants taking up my windowsills as it is- but i just cant resist. I have to decide what plants to get next so i can start them :)