Seed packets are available to buy for some varieties of chrysanthemums. 'Chrysanthemum seeds can be sown directly in the garden in early spring, or indoors 6-8 weeks before the last frost date,' says Autumn Hilliard-Knapp of Perfect Plants Nursery.
'Sow the seeds on the soil surface, lightly press them in, and cover them with a thin layer of soil. Keep the soil consistently moist but not waterlogged. Once the seedlings have a few sets of true leaves, thin them out to allow proper spacing.'