Transplant to recycled six plant packs or similar containers when the seedlings are large enough to handle. An alternative to starting the plants in containers is to sow the seed outdoors in a permanent location. After the plants have germinated, thin to the proper spacing for that particular cultivar. If you provide optimum growing conditions the triploids and many French cultivars will begin to flower seven to nine weeks after you sow the seed. However, availability may be restricted to one or two mail order seed sources.
Marigolds are subject to far fewer insect and disease problems than most annual flowers.
Young marigold plants can rapidly be consumed by these pests.