Soil Type Average, well-drained Days to Germination: 7 - 10 Days at or near 90 (faster if soaking seeds in warm water overnight) Days to Maturity: 70 - 80 Days If you do allow the plants to self-seed, thin the newly emerging seedlings to allow at least 18 inches between plants. This improves the vigor of individual plants, encouraging the most blossoms from each plant. If you want to limit cleome?s self-seeding habit, remove the long seed pods that form. USA SELLER FAST SHIPPING Order now and start growing your own Plains Coreopsis to enjoy its benefits and beauty.