Hi there,
I have grown just the species. It is pretty resilient, can compete with tree roots ( well, to a degree), but in shade it tends to sprawl. They keel over and grow towards the light.

It is good for larger beds and is IMO not a very neat plant for formal situations.

And it is not a very late Aster.

All in all I think it's great. I do a monitoring of a couple of perennial plantings at the moment. One is under three Gleditschia trees (Locust?), a quite new planting, most plants looked ratty and the Aster d was looking happy.

Bye, Lin

Symphyotrichum cordifolium AKA Aster cordifolius AKA blue wood aster is another fall aster that's perfectly happy in shade. It's native here but I let a few grow in some of the shady gardens. In my garden it grows to 2' or 3' and it stays pretty well controlled if I deadhead it. Otherwise it tends to seed around.

In this spot it has sun for several hours.

Don't know about the cultivar you mention, but the species, certainly semi-shade, Rouge.

Some of it is still in bloom in our own garden.

Find it a very useful ground cover.

My only criticism is that because of a sprawling habit, it can trip you up when your working around it. I do always cut the plant right back (and usually reduce the area of it) in fall.

Below (September 2, 2013).

Correct nomenclature aside, I find that both Aster divaricatus and Aster cordifolius are excellent shade performers. They are both a bit rangy, true enough, but they are attractive enough in other ways that their ranginess doesn't really matter much, IMHO.

Aster divaricatus started blooming for me in early-mid August but did not reach a crescendo until mid September. My plants still have many blooms right now. I love the contrast of the dark stems with the dark green foliage. This is not a showstopping plant, but is a wonderful and easy to please mingler. Still to come are the delightful, fluffy seedheads that will last until spring.

Aster cordifolius is in full bloom now for me. It is much taller than A. divaricatus. Some of the foliage is assuming striking burgundy tints which looks incredible with the cloud of pale mauve/blue/lavender flowers hovering overhead. Two minor cons, though. I found quite a few seedlings this spring, mostly very easy to remove where not wanted. Second, my plants were targeted mercilessly by rabbits this season so only 4 out of 10 plants were strong enough to bloom this season.

You can't go wrong with either of these. They seem to perform just as well in deep shade with little direct sunlight as in filtered or partial shade.

Aster divaricatus (Eurybia divaricata) can easily take dry or moist shade. The flowers are not very showy and it is a sprawler when grown in the shade. However it serves the purpose of a groundcover very well and rarely needs watering or any special care. Aster cordifolius (Symphyotrichum cordifolium) also grows in part shade, but has showier flowers, grows more upright and self seeds vigorously. It's common name is Blue Woodland Aster.

'Sunny' and 'babs' those are excellent, telling pictures. Thank you.

Great info 'ispahan' and 'ontnative'.

I have made a note to at the least consider a "Blue Woodland" Aster in a part shade location in 2014.

I learn so much from many of you. Thanks again.

This post was edited by rouge21 on Sat, Oct 26, 13 at 16:49

Was thinking of trying Symphyotrichum (Aster) cordifolium.

Liked Ontnative's useful information until I saw "self seeds vigorously". Maybe it wouldn't here, but I won't be risking it.

Eurybia (Aster) divaricata spreads here, relatively vigorously, but I've not noticed it self seeding. It's also very easy to chop away portions of it with a spade.

I don't think my eurybia (aster) divaricata self-seeds either. I'm not sure why, but I'm not complaining. That's one thing I have against growing native plants. Most of them self-seed way too much. Bad for me, and bad for my neighbours, who like to grow grass in their front yards.

I find that Symphyotrichum (Aster) cordifolium self-seeds, but not so vigorously that it's a pest IME. I find it less of a problem than tall phlox or Lobelia siphilitica in my garden. If I take the time to deadhead, I get few seedlings, perhaps because often the bloom is late enough that many seeds don't develop, and I find the seedlings relatively easy to pull.

Re Ontnative's complaint against growing native plants (in gardens); namely, "Most of them self-seed way too much".

I'm in 100% agreement.

It's one thing that these plants do well (for themselves) in a particular environment, but they often spectacularly well in flower beds, carefully prepared by gardeners.

A number of more floriferous introduced species perennials may also become rampant self-seeders in gardens (rose mallow, musk mallow, Kashmir tree mallow, knautia, etc.). I'd assume that they too do better in our gardens than they do in their native habitats.

Sometimes using selected cultivars of species avoids the problem. Using sterile cultivars always does!

It may be that native plants self seed more, it does make sense that they would, yet, many plants that are not native self seed as well. And if they are actually sterile, then they are not capable of providing pollen for bees, isn't that right?

Some of the best plants for pollinators are natives. For instance, it was brought to my attention that potted mums that we buy in the fall, are not attractive to pollinators. I had not thought of that before, so I watched my plants to see if the bees were visiting them and sure enough, on the doubles, they were not. They were however all over another mum that I have that is a single blossom chrysanthemum, and they were all over native asters.

After that I noticed that my favorite marigold, which is a white double that is very puffy, was not feeding pollinators either. Bees would land on it and search for pollen and not find it and fly off.

I read that goldenrod is the most popular plant for many many pollinators, and I don't grow goldenrod because of it's ability to travel and self seed. So, I am trying to find the balance between saving myself some work and helping out the bees that are struggling.

Assume the spread of native plant seedlings, in the wild, is limited by animal consumers and probably especially by other native plants (latter: re adjacent microclimates).

I do favour the use of sterile plants, but also use many very useful North American perennials which are bee magnets (not least New England aster cultivars, as PM2 indicates).

For me, two summer bee magnets are culver's root and purple loosestrife (only use the latter very carefully).

I realize that wild asters and goldenrod can spread like crazy in gardens, though for me, running rather than seeding seemed to be the main problem.

I do think that many cultivars which have been selected for clump-forming (and against running) work out very well in maintained mixed perennial gardens.

Picture below (set up on October 5, 2013, for a wedding) has the wrinkled-leaf goldenrod 'Fireworks' (on the right), planted in 2006. I've seen no seeding from that cultivar and it's spreading is quite tame. It's very easy to pull up. There's more of it there than I would usually leave because the garden is not maintained that intensively.

I've seen Aster divaricatus growing in wild areas that were pretty much full shade, but I don't have any growing in the gardens. Got lots of Aster cordifolius and love it. It blooms in patches here and there in the shady areas and creates a haze of lavender blooms which the bumblebees love. It is one of the few native plants that grows and blooms well in nearly full shade, directly underneath a Silver maple, and in the middle of the Vinca minor. Very tough! It seeds around, but not so terribly, and I like having more natural gardens, especially in the back yard.

Btw there are species of Goldenrod that are clumping and much less aggressive than the rhizomatous Solidago canadensis. I really like Solidago speciosa, it's a very pretty clumping species (prefers full sun though).