I've always been amazed at the group of grasses called Carex. They take full shade, bloom in early spring and require absolutely no maintenance in my USDA Zone 5A garden.
You can see from the photo I took of 'Ice Dance' this week, how good it looked after the snow subsided - unlike many of the hot weather grasses that had collapsed and turned a dull tan. Carex morrowii 'Ice Dance' is a good clumper and stays within its bounds. I've had this plant for over 5 years and it is about 50 cm wide and 40 cm high. Whether you decide to use it to brighten a dark corner, or just provide some dependable colour along a front path, you'll be happy with this plant's performance.