Delphinium Seeds - Delphinium (Larkspur) ajacis Frosted Skies Seeds Ref: TM01402930 SowingBest sown where they are to flower in spring, or late summer/early autumn for overwintering. Sow 3mm (1/8in) deep in rows 30cm (12in) apart in well cultivated soil which has been raked to a fine tilth.GrowingThin out the seedlings to 23cm (9in) apart. They prefer a deep rich soil in full sun on heavy soil.Aftercare Autumn sown plants should be transferred to a coldframe for the winter and planted out in spring.FloweringSummercroppingPlant typeHardy Annual Price: £2.09 Quantity: