Posted: 21/06/2013 at 16:53
Depends on the variety, tag. I grow Amsterdam Forcing which are an early-maturing variety and they can take 70 days to maturity. They usually germinate within 10 days.
Carrots need soil that's deep enough to more than accommodate the length of the carrot and free of lumps, pebbles, rocks, etc.
Sowing in Jan-March? I don't sow mine before April here in central Italy. The soil needs to be warm enough for them to germinate.