Sow the seed thinly, direct into finely raked, moist, warm, weed-free soil where the plants are to flower at a depth of 6mm (¼"). Germination normally takes 10-14 days. As the young seedlings develop, thin in stages to achieve a final spacing of 30cm (12"). Use any spare plants to fill gaps in the rows. Make successional sowings for summer long scent.