Although I have gunnera manicota seeds, I've never sown them. But since they are considered a tropical/tender perennial, I would wait to sow them until March. The info lists it as a boggy plant, but don't think the seeds could necessarily take the freeze and thaw of winter weather. That's my two-cents worth.
Do you know what type of gunnera seeds you have?

PV

Yes they are the manicota.Everything I have read says that they need to be fresh seeds.I may sow a few now and more in March and see what happens.I want this plant so bad!!!!Thanks for your help..

Vels, if you have enough to sow more than once, maybe try some, but they don't sound like an especially good candidate for winter sowing.

Clothiers: Gunnera manicata, scabra, and tinctoria , Sow 75-86F, germination in about 2 weeks

But most germination databases mention what you said, short viability. I checked propagation notes in Hinkley's Explorer's Garden ( Perennials edition) for you and the notes only read - sown fresh the seeds will germinate almost immediately. He also mentions handled fresh, they will stain your hands and clothing ;)

I put in a plant in Fall, it should be winter hardy here. We've had a freeze that shouldn't be too much for it, but I'm concerned about how much rain its been exposed to (more than 6" in one 24 hr period two weeks ago). Cultivation notes indicate the crown doesn't like winter wet, and the crown doesn't feel healthy to me this weekend (gentle squeeze test). If it doesn't work out I'll try again. I have room for the plant finally, I would like to try growing it...

Thanks morz,Im gonna check the seeds in water to see if they are viable.We will see what happens.Good luck with yours.
Velvet,velsgarden