Our Zinnia Choice Mixed seeds are the best that zinnias have to offer. Perfect for bright summer borders, the flowers have the boldest colours and most exotic forms and are all extremely long flowering. Outdoor sowing: Sow thinly in a seed bed in flowering position in rows 30cm (12in) apart. Cover lightly with fine soil. Firm gently and keep moist. When large enough, thin to 25cm (10in) apart. Keep moist and weed-free. Indoor sowing: Sow thinly in trays of seed compost, cover with a fine layer of compost, firm gently and keep moist. Cover with glass, polythene or propagator lid and keep at approx. 15-20°C (60-68°F). Seedlings usually appear in 7-14 days. Growing on, remove the cover when seedlings appear and grow on at approx. 10-15°C (50-60°F). When large enough, transplant 5cm (2in) apart in trays. Stand outside for a few days in late May (avoid frosts). Transplant 25cm (10in) apart in flowering position. TIP: Avoid root disturbance when planting out.