Carrots require a loose, rich soil and consistent moisture for best production. Plant seed 1/4 inch deep in rows 12-18 inches apart, thinning seedlings to 2-3 inches apart. Cover seed with a loose soil and avoid crusting by compaction or heavy water before seeds sprout. Germination is best at soil temperatures of 60-75 F. Use successive plantings 2-3 weeks apart for a longer harvest season.