'Yaku Jima' is a dwarf variety of M.s. 'Gracillimus.' It should only reach 4' in foliage height and 5' to the plumes.

My 3 y.o. Yaku Jima is most definitely not a dwarf, the tallest plumes are right at 7'-ish! Here is a recent pic.~

{{gwi:871934}}

7 feet tall??? Oh my!
Juicylucy, how wide is your (just beautiful) grass?

I recently bought one Dwarf Yaku Jima too, and only because the nursery assured me it was a very small variety. In effect my DYJ is very little now, but it is still a baby!

Another question about it, please. Is it normal that its plumes take a long time to open, I mean to fully bloom? They appeared 2-3 weeks ago and are still 'closed'..

I haven't seen Yaku Jima get that tall before. It would be pretty easy for a nursery to mix up pots of Yaku Jima and other maiden grasses.

Yaku Jima usually does not have flowers that reach much higher than a foot or so above the foliage, but planting conditions can make a big difference in how a grass matures, so who knows. All of the Yaku Jima ive planted has been what I consider a dwarf miscanthus, blooming under the 6 ft mark.

The Yaku Jima pictured sure is a spectacular looking miscanthus!

If youre looking for a real dwarf miscanthus, try Little Kitten. I really like it, as it gives the tell tale miscanthus seed head, but is truly a compact small garden grass.

Also, Adagio I think is more compact and tight growing than Yaku Jima. The foliage gets a little longer and wild flowing in Yaku Jima (best descriptive I can use lol). Adagio is a more uniform grower.