Hi, Kate. I don't know what is hardy in your zone, but I have two very shady bog gardens and in them I have all kinds of blooming and non-blooming plants that thrive. Hosta, daylilies (many varieties), lots and lots of ferns, hardy geranium, obedient plant (can be invasive), canna, water celery (also can be invasive), violets, hibiscus, pee gee hydrangea, pussy willow, Louisiana & dutch iris, calla lilies, creeping jenny & astilbe. We are presently building another bog garden in yet another area of our yard that will not grow grass. I love bog gardening. For me, it is the most reward for the least amount of work in all my gardening. Don't throw in the towel yet.

Here is a list that I've posted before. Appears pretty comprehensive.

Hi, I have a natural bog garden at the back of my lot. We are learning to live with it as we are the lowest point in the neighbourhood and it used to be a natural stream in spring. You can't fight nature!

I have planted blue flag iris, and 2 types of filipendula (venustra and a small, fern-like one), both of which are exceedingly happy. Some pulmonaria and hosta are growing nearby. Have loads of ferns naturally as well. This year I'm trying toad lilies.

My problem is trees. We want more trees back there but everything we plant apart from ash dies.

Hi, quirkybec; what ferns are doing well in you Zone 4/5 bog? Royal? Cinnamon? Interupted? anything else? I need some ferns for a shady area bordering a natural pond which is rather boggy and smelly at this time of the year. Thanks.