Seed Plants: Angiosperms Introductory Biology Cascading Plants That Spill Over Pots, Beds, Walls & Borders Gardening Know How Burpee All Seasons Organic Cabbage Seeds Green, 1 ct Fred Meyer How to Harvest and Save Moonflower Vine Seeds 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