Sow marigold seeds directly in the garden once there is no danger of frost. Pick a spot with full sun and well-drained, aerated soil. Thin young plants to allow ample space between marigolds.Continue Reading
Choose a planting area that gets plenty of sunshine. It should have well-drained soil. When planting marigolds in containers, use a soil-based potting mix. Plant slower-growing American marigolds after the danger of frost has passed in spring. Plant faster-growing signet or French marigolds anytime between spring and midsummer.
Till or dig the soil in the planting area to depths of approximately 6 inches. Discard any debris or stones in the soil. Mix an all-purpose granular fertilizer into the soil.
Sow the seeds directly in the garden, allowing 1 inch of space between the seeds. Water the newly planted seeds after planting them.
Once the plants reach heights of 2 inches, thin them out to allow 8 to 12 inches of space between the plants. Container-grown marigolds should also be thinned to allow ample space between plants.
Water the marigolds regularly, allowing the soil to dry out a bit between waterings. Avoid watering from overhead. Instead, water at the base of each plant.
Deadheading American marigolds keeps each plant looking tidy while stimulating continual blooming. To maximize each plant's flowering potential, do not apply fertilizer after you have planted the marigolds.