I can't figure what what plants would be great companions under a very red maple.
Please give me some suggestions, especially on perennials.
Thanks so much
Black mondo grass possibly?
Depends upon your personal taste.
I would not go for the black mondo as it is too dark/ brooding under a redleaved tree.
Prefer something brighter,
A greygreen would be subtle contrast, with an Geranium renardii (what is the soil like, by the way.),
Some golden green cheerful contrast, with some medium, solid goldengreen Hosta (August moon),
How important is an winter aspect, do Hellebores grow in Z5 .
Chuck in some details, perhaps something usefull for you might pop up,
I have Emerald and Gold euonymus under a red Japanese maple, and it looks very nice. Good contrast.
Forget color...what can grow in that much shade and with that much root competition?
I'd go with ferns and spring bulbs. Japanese painted ferns, red beauty ferns, grape hyacinth, trillium?
Hakone grass is a nice companion. I have a golden one (three plants) that grows well under dappled shade. It cascades beautifully if among some rocks. In my zone 5 it has stayed in control with a bit of spread. Actually wish it would take off a bit more.