1) A full grown hellebore (H.x hybridus) will take a three foot square.
2) In your zone it should take three years for H.x hybridus.
3) Helleborus x hybridus likes fertilizer, any kind, they are a very hungry plant.
4) More sun than you think they need. In good, deep, humus soil, with irrigation in dry spells, Helleborus x hybridus in your zone will thrive in full sun.

Welcome to the hellebore forum, good luck with your seedlings. Are they Helleborus x hybridus?

Always Gardening,
bruceNH

THANKS for the response. My friend gave me a call from the road, and I asked him about the hellebores... told him I posted to this forum..... and he got them from Washington, not Michigan, and he made the seeds from seedlings he selected out there. Boy was I way off on my info! I don't know what hybrids they are. But, when I visited my friend earlier this spring, he showed me the seedlings he selected and brought back. FABULOUS array of shapes and colors... one was a near white with pink picotee edge. I hope to get the images I took that day up on my web page, and when I do I'll post back to this forum. I am glad they can take sun - I don't have enough shade for 30 plants 3 feet across! The soil they are in has had composted manure, alfalfa pellets, and hardwood mulch tilled into the soil a year or so ago. The daylilies thrive there, so am hoping the hellebores will to.
Jules

Sounds like you have good taste in friends....