Crystal I find the best time is about 6-8 weeks before Spring... probably about the first of February in your area. The seedlings should then be big enough to go in the ground after the last frost, and grow full size by the end of summer.
not at all...the hardy hibiscus are some of the easiest seeds of all to sow. Just put them about 1/2" down into moist potting soil in small containers and let them sprout. you can transplant into larger containers when they are larger.