Dianthus Seeds - deltoides Brilliancy Seeds Ref: TM01403165 SowingSow spring to autumn in good free draining seed compost, just covering the seed with compost. Germination usually takes 14-30 days at 16-21C (60-70F).GrowingWhen the seedlings are large enough to handle transplant into 8cm (3in) pots, grow cool and finally plant out 15-20cm (6-8in) apart into a sunny spot in free draining soil.Aftercare Overwinter autumn sown plants in a well ventilated coldframe and plant out in spring.FloweringSummercroppingPlant typeHardy Herbaceous Perennial Price: £2.19 Quantity: