I had Erianthus Ravennae for about six years. Every year it was a spectacular site. Cut back in spring, never had any seedings. BUT in six years if memory serves me well, she was 5-6 feet across at the bottom and 12 feet tall. Cutting it back was incredibly painful. Not as in difficult (it hurt). So it had to go but still miss the sight of her sometimes. Pat

I had Erianthus Ravennae for about six years. Every year it was a spectacular site. Cut back in spring, never had any seedings. BUT in six years if memory serves me well, she was 5-6 feet across at the bottom and 12 feet tall. Cutting it back was incredibly painful. Not as in difficult (it hurt). So it had to go but still miss the sight of her sometimes. Pat

Bear grass - Xerophyllum tenax - is not a grass but a perennial in the lily family. It spreads primarily by rhizomes. It has a very periodic flowering cycle of about every 5 to 7 years so obviously not a lot of self-sowing going on. I have never heard of it being invasive (as a US native, it doesn't really fit that definition) but in the wild it does form large colonies.

Yeah, I know bear grass isn't technically a grass but without a flower it's near impossible to tell a difference because of its fine blades. I was wondering if it would get out of control in a garden bed bc it's always so prolific in images of it growing wild. My money would probably be better spent on Eremurus roots; that way I'd get an impressive flower every year.

pattyw5, thanks for the forewarning about cutting it back. My initial idea was to plant clumping or running bamboo in barrels(something i still might do just not more then one)which will require significantly more maintenance particularly they're not a lot of hardy verities. But I've definitely fallen in love with the idea of Erianthus.

Would you always cut it back before the seeds would start to fall?

I have three big clumps of Ravenna, which I started from seed. The plume stalks hit 14' this year. I built a bamboo 'cage' around the clumps to help keep them upright in our windy climate. It's a beautiful sight, and although Hurricane Sandy defeated the bamboo, it didn't knock the Ravenna down. I was just watching Sparrows riding the plumes in the breeze, plucking off seeds.

Even though I grew them from seed, they have never self-sown. The clumps just get wider and wider each year. I cut them down in early spring, and cut the canes into usable lengths for garden supports, and 1" pieces for mulch.