Sow the seed thinly direct into finely raked, moist, warm, weed free soil where the plants are to flower, 6mm (¼") deep. Germination 14-30 days. As the seedlings develop thin them in stages to achieve a final spacing of 20cm (8"). Use the spare plants to fill any spaces. Remove any weeds as they develop, but be careful not to disturb the young plants.