Blue nigella - A rom-com of the garden, these sky-blue beauties, may look wispy and delicate, but nigella is no damsel in distress and will be hardy to an English frost.

It's why it's special: 

• Nigella seeds are easy to germinate and quick to grow.
• A long season of blooms, even in the cooler months.
• Blooms make for excellent cut or dried flowers for your home with sculptural seed pods.
• Makes for great ground coverage over spring bulbs.