Zinnias are easy to grow and can be sown directly outdoors. The small, pompom flowers are produced in a range of colours and are loved by bees and butterflies! An excellent border filler, or try some in patio pots.Sow seeds on the surface of a good, free-draining, damp, seed compost. Lightly cover, 3mm (1/8in) deep with vermiculite or compost. Place container in a propagator or seal inside a polythene bag at 20-30C (68-86F) until after germination which usually takes 7-14 days. Can also be sown direct into the soil after last frost.Transplant seedlings when large enough to handle, taking care not to damage the fragile roots, into trays or 7.5cm (3in) pots. Gradually acclimatise plants to cooler conditions for a few weeks before planting out after all risk of frost 30cm (12in) apart.