Wild Rose Seed Packet Nigella is one of those flowers that actually prefers the cool soil of early spring. In Zone 6b, I start sowing my nigella seeds in late winter and continue sowing through early NZND Plastic Pots for Indoor Outdoor Plants, Garden Seedling Nursery Planter, 1 2.2 3.2 Gallon, White Walmart.com How to Keep Chipmunks Out of Your Garden, According to Experts