Sow Larkspur Giant Imperial Mixed seeds directly outdoors, where they are to flower, in well-prepared, pre-watered soil. When seedlings appear, thin them to 25cm apart and water well until plants are established. Sow from March to May, and your Larkspurs will flower the same year; alternatively, sow from August to October for earlier blooms next year. Repeat sowings at 2-3 week intervals for a continuous display.

Larkspur seeds typically take around 14-28 days to germinate. They won’t sprout if the soil temperature is too high, so sow them directly outdoors in spring or autumn for the surest results. Refrigerating the seeds for a week before sowing can help encourage germination.

Yes, like most annual flowers, Larkspurs (including Larkspur Giant Imperial) will self-seed if given the chance. Any flower spikes left on the plant will run to seed in autumn, rewarding you with new seedlings next spring. Once they emerge, you can move your Larkspur seedlings to a sunny spot to continue growing.