Saving seeds from carrots is difficult, especially if you live in an area where wild carrot is prevalent. Carrot is a biennial, so it takes the plant two years to form seed. It also easily crosses with other carrot plants, which can lead to undesirable traits in the seeds. If you wish to try seed saving as an experiment or because your favorite carrot variety is hard to find, plan your garden so the carrots do not grow near any other types of wild or domestic stock.
Dig up the carrots you are saving as seed stock the first fall after planting. Dig them up before the ground freezes, but after the tops yellow and begin to die back.
Fill a large tub or bucket with slightly moist sand. Bury the carrot roots in the sand and place the bucket in a protected area outdoors. Keep the sand slightly moist, but do not allow it to get overly damp or soggy.
Replant the carrots in the garden bed in spring once the ground thaws and all danger of hard freeze is past. Space them 8 to 12 inches apart, as the roots get very large this second year. Plant the carrot roots to the same depth they were at previous to digging them up.
Cut off the seed heads with garden shears in mid-summer once the flowers wither and the seed heads begin to dry. Lay the seed heads in a bowl and place them in a warm, dry room to finish curing for an additional one to two weeks.
Remove the seeds from the seed heads and place them in an envelope or jar. Label the envelope with the type of carrot and the year harvested then store the seeds sealed in a cool, dry place until you are ready to replant.