What plants are appropriate for wet, clayish soil in deep shade?

I’ve been trying to work with a shade garden in a big area next to my garage that won’t grow grass. The previous owners have some daffodils and hostas there, and they do fine. I added wild ginger, which is hanging on, and tried a lot of other things - mostly ferns - that simply didn’t handle the long winter. Or maybe they did, but I haven’t seen any sign of them at all!

In any case, there are still a lot of big empty spots and I’m looking for more things to add. I like the wild ginger, but it doesn’t grow well from seed and the only supplier I found locally charges like $8 for a small plant, and I’d need dozens and dozens to fill the space. And besides, it’s not really thriving.

I’m in Zone 5 and I would like it to overwinter. Ideally, I’d like things that can be grown from seed so I can order online, since greenhouses in my area tend to have limited selections. (I’ve never had much luck ordering live plants.)

Ideally, I’d like groundcover, but am open to anything that doesn’t require too much maintenance and can survive in these conditions. I do add plenty of compost and soil when I plant but this area gets some runoff from the garage so it’s hard to keep it from getting clayish again.

I’m no expert, but you might try ferns. I live in a cold climate (Minnesota), and the soil in our yard is very clayish. The ferns love the north side of our house and garage. The hostas we planted there also seem to be doing well.

Lily of the valley are good shade plants. It’s been forever since I’ve had them (they used to fill my parent’s side yard but they’ve long since been mistreated to the point of epic growth failure), so I don’t know for sure how they do in heavy clay. But my parents live in an anticline valley in the Allegheny Mountains, and the whole damn place is at least medium clay, so they should do fine.

Hostas are very popular around here; we’re zone 7, though.

You do have three major problems all working against growing stuff.

Ranunculus (buttercup) of some type may do alright.

Wood Violets

Jack in the Pulpit

Mayapple

Ferns

Wild Ginger

A couple inch layer of organic peat would help you out greatly. Many wild plants like I just listed do well in what you listed if they have the organic peat layer. You still have a chance with those plants even if you don’t add the organic peat.

The ginger should stay, and the ferns that look dead right now will probably surprise you in a month. After a couple years ferns will be almost impossible to get rid of. Pick ones that are in the size range you want. I doubt you want 4 foot tall ferns, but may be wrong.

What soil there is under our horrible Norway maples is thin, and red clay. If you don’t mind them spreading, you might try violets. We have an eye-popping beautiful carpet of purple (and a few white) violets late in the spring. They bloom before the trees leaf in.

English Ivy looks great as a ground cover and will grow practically anywhere with little fuss. However, you do need to stay on top of it and cut back drastically from time to time, especially if you have brick siding on your house (unless you want it to crawl up onto your house).

I love it because nothing else will grow on the north side of my house and for the most part it stays green all winter (I’m in zone 6 so I don’t know if it would stay green in zone 5).

Make sure you really like it though! Maybe try it in a small area first because once it gets fully established, good luck getting rid of it.

Hostas are also very popular here in Zone 3, so I’d say they would be fine (as she says, she already has some in her yard). You could also try some goatsbeard (Aruncus dioicus). Willows usually like moist conditions; I don’t know if they’d be happy in the shade, though (you can find some smaller ones like Salix purpurea).

Maybe some pulmonaria, ligularia, or irises? Violas grow everywhere. Maybe some moss, too.

Another vote for amending the soil with some organic matter. The problem with heavy clay is that it holds water, and that promotes root rot. That could be what happened to your ferns. I’m in Zone 5, and I’ve got tons of ferns and wild ginger, but we are fortunate not to have clay soil.

Lamium prefers well-drained soil, but it does well in shade and it’s in the mint family, so you know what that means!

I love Solomon’s Seal, and it does well in damp, shaded soil, but it likes organic matter. It’s not really “ground cover,” but it will spread.

Another vote for Lily of the Valley. Try planting them in with your hostas. The Lily of the Valleys will bloom while the hostas are still short, and then the hosta will grow up and hide the lily of the valleys for the rest of the summer, when they are less good looking.