I'm not as warm as you, so I don't know how much this will help you. I have my astrantias intermixed with my aquilegias on the west side outside edge of a hosta bed which is under a very densely branched tree (heavy shade directly under the tree). The astrantias & columbines get lots of sun in the spring before the tree leafs out and some shade the rest of the season from the overhead branches early in the day & the slanty late afternoon sun. There is bright light on that edge of the tree most of the day, but little direct mid-afternoon sun. This kind of odd light situation seems to suit both the columbines and the astrantias very well and since they bloom at different times they make a nice long lasting combo, both varieties giving a similar look throughout the season. As for the astrantia foliage, I have to admit I don't pay much attention to it since Hosta Titanic is in that area with its huge leaves. The bed is watered by soaker hoses and the darkest interior area is planted with epimediums, maidenhair ferns, toad lilies, and a spreading variety of tiarella. Sweet woodruff (Galium odoratum), a notorious spreader, gradually died out in these conditions, but all the rest of these plants all do well here!

I'm afraid I'm not going to be of any help here, woods. I've had mine for probably over 5 years - they've multiplied through the years into more plants than I need or want. In all this time, I had ONE BLOOM! Why do I keep them??!! Because of that one fabulous bloom that smelled like heaven and had visions of getting hundreds more just like it next year. With that one bloom, I was sure I had something really good going on, lol. So I moved them all to what I thought was a better location - prime garden spot - and pampered them. The result 3 years later is a big fat nothing - just more plants. I don't think our NC cold (not that bad) is a factor, and I think our NC growing season is long enough. I think they do best in a sunny, hot and dry location with poor soil and complete neglect. At least that's what was going on when I had my one bloom. So this week I'm moving them all back to the slums - back to the sunny, gritty and dry netherlands of their former location and I vow to forget about them. Maybe this plant with its delicate and glamorous-looking flower and scent is actually a toughie that prefers adversity?

Mags, I'm not too sure of your zone, but, out here, I have moss between my stones and it is happy living in the clay. However, the parts that get the mid-afternoon and afternoon shade are quite mossier than the parts that get all day southern sun, and, the parts that get the most sun do not hold anything but weeds. Also, the moss seems to live even when it pops out. How to explain?...little clumps of it pop out from between the stones and just lie on top, happy and green. I think my dogs claw at it, pee on it and such. Not sure the roots are that deep. I hope that helps! J

I have the identical situation to yours. I use window boxes on my deck rails and these are the plants I have had wonderful results with: Salvia farinacea, Victoria and her kin Blue Scaevola: excellent trailer (Have tried whites twice with very poor results. Go figure.) Annual Vincas Million Bells Melampodium Profusion Zinnias Sweet Potato Vines, good trailers Pansies in winter and early spring marigolds (usually have to replant in mid summer due to insects, but I use them instead of mums for fall) Plectranthus, Cuban Oregano, good trailer Petunia integrifolia is good in spring. It reseeds too. I also grow oregano, thyme, and basil in these pots for cooking purposes, and in the winter, I grow leaf lettuces which I can usually harvest all through the winter.