Direct sow stocks outdoors where they are to grow from April to July. Choose a position in full sun on any well drained soil which has been raked to a fine tilth. Sow seeds thinly, at a depth of 6mm (¼in) in drills spaced 30cm (12”) apart and cover the seed with its own depth of soil to exclude light. Water the ground regularly, especially during dry periods. Germination usually takes 7 - 14 days. When stock seedlings are large enough to handle, thin them out to 30cm (12”) apart.
Feed and water plants regularly. Deadhead faded stock flowers to encourage more blooms to be produced.