Delphinium (Larkspur) Seeds ajacis T&M Improved Ref: TM01402976 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 will grow best in sun and in a deep rich, moist yet well drained soil.Aftercare On heavy soils autumn sown plants are best overwintered in a coldframe and planted out in spring.FloweringSummercroppingPlant typeHardy Annual Price: £1.69 Quantity: