The most well behaved plant in my garden has to be Aruncus aethusifolius. The plant catalog at my desk here describes it perfectly: "10" compact mounds of dense, finely cut foliage, miniature spires of creamy white".
It forms a perfectly round mound, looking as if a garden gnome came upon it in the middle of the night and trimmed it.
Right now (June 10th) it is in full bloom. The blooms last a pretty long time, I'll be watching carefully this year to see how long they are here. Gradually they fade to a tan color and I just leave them on the plant since they remain nice and neat.
I also love the fact they they will scatter a few seeds this way although I never get as many seedlings as I'd like to get.
Last year I added two more types of Aruncus to my garden. This photo shows Aruncus 'Misty Lace' which is described as a " 2' X 2', compact and heat tolerant, deep green Astilbe-like foliage topped with delicate pure white plumes.
Sure enough it too is behaving as perfecly as it's little sister. It's just a bit larger than the athusifolius variety and has even more blooms.
I have this one in part shade, it gets lots of direct morning sun but no afternoon sun and it is as happy as can be.
Here's another angle, I love how it looks against the deep purple foliage of the Ligularia 'Britt Marie Crawford'.
The last variety of Aruncus in my garden is Aruncus dioicus which is the large version. 4-6' tall giant cream plumes in July, foliage looks like a giant Astilbe is just about the perfect description. What the catalog doesn't tell you is how wonderful this looks in the landscape.
For many years I walked past the pots of this giant Aruncus at nursery centers. It looks awful in pots. The blooms sprawled all over and seemed dingy in color. In the garden though it's a whole different story. The creamy white is just dreamy and the soft arching blooms are so much better than I ever imagined.
Sitting here typing on my laptop I can look out my dining room window and see it in full bloom. It looks magnificent and I hope it too gives me some seedlings like the athusifolius variety has done.