Fill a seed tray, seed flat or small starter seed pots with potting soil. Moisten each section with water. Set several seeds per pot. By putting a few in each pot, you can later thin out the strongest seedlings.
Cover the seeds with a thin layer of soil -- 1/8 to 1/4 inch is sufficient to encourage germination. Put the trays, flats or pots in a sunny spot in your home, such as a windowsill.
Water the seeds regularly to keep the soil moist to the touch. Seedlings will be strong enough to move outdoors in a few weeks.
Choose a sunny garden location for the coxcomb. It should get at least six hours of sunlight daily. Aerate the soil with garden tools to loosen it and break up large clumps. Mix in peat moss to improve drainage. Wet soil will cause coxcomb to experience root rot.
Dig a hole large enough for the flower's root mass. Place the small plant in the hole and cover loosely with soil. Water until the soil is moist, but not soggy. Insert a finger into the ground to determine when you have watered it enough.
Fertilize coxcomb flowers after two weeks with a water-soluble liquid formula. Follow the instructions on the label.