I plant them every year. I just buy a seed packet and follow directions for planting. The package will tell you to thin them out as they start growing. I don't follow that bit of advice. As the green parts start getting bigger I dig around the side of the rows with my hand and carefully take out the largest ones and push the dirt back around the rest. At first they aren't that big but you get a lot of baby carrots to eat whole this way, and as you do this the row is being thinned out with a lot less waste. Also If you let some go to seed you will have volunteers next year. I feed a lot of these babies to my dogs. They absolutely ADORE carrots.