could be used either straight or mixed BUT YOU SHOULD/MUST STERILIZE THE COMPOST FIRST.

Use 2/1 peat moss/perlite or vermiculite. They are cheap and for the most part sterile. I've had great germination rates with the peat/perlite mix. This year I added course sand to the mix and got even better germination and faster growth. I don't know if it was the sand or the seeds but most of the seeds were saved from last year. Mix the compost in after the first set of true leaves appear. Germination is better w/o the rich compost. Seed starting mix has no or very little nutrients.

gemfire, I've tried it, and they did OK, but not as well as in peat pellets. (My compost was fairly fresh, free of recognizable particles, but still pretty chunky, and I did not sterilize it). I think the jiffy pellets work better because they have small particles that the sprouts can easily push through. Not sure why, but they work better for me than regular peat.