I have been told not more than a third, Margaret. I have so few in containers now as this is a job that got to be too much for me. It is getting to be "that" time, and I can hardly wait for my inground ones to emerge.

Carrie...it surely would be nice to leave them in the
ground, but I have to winter over. They do so much better.
It'll probably be 1/3 in the ground and the rest in pots. It
is indeed a job to take them up, so, I must work smart.
I'm sharing a couple of the singles with my two brothers,
who lives close to me.
I'm planning to try plunging some of the pots in holes
that have been dug already. You see....I'm planning
ahead
I was thinking about a 1/3 trim also...Thanks!

I suppose I stay a little warmer than you (it has been in the seventies this week and that has been wonderful) and our freezes aren't as long lived. That is why I have most of mine inground even though they don't bloom as early. I keep a few in containers for early blooms. My Dr. Seuss will grow into a "tree" in one season and blooms for several months. When I first started growing these beauties, I was much younger and loved the extra work to get them to bloom to their fullest......................now, I have had to scale back so I can care for the ones I have.