The marigold is an annual flowering plant from the daisy family and is native to South America and areas in the Southwest United States. Marigolds produce large seeds, making them easy to handle and sow in early spring. Sow marigold seeds indoors about eight weeks prior to the desired outdoor planting date or sow marigold seeds directly in flower gardens in warm growing zones where there is no longer a risk of frost in early spring.
Fill a seed germination tray with a moist germination or seed starting soil. Sprinkle the seeds over the top of the soil so there is a 1-inch space between each seed. Cover the marigold seeds with approximately 1/8 inch of moist seed starting soil.
Place the tray in a warm location with a temperature of 75 to 80 degrees F until the marigold sprouts appear. Marigold seed germination occurs in three to five days. Monitor the soil to make sure it remains evenly moist during the germination process.
Move the germination tray to a sunny location with a temperature of 68 to 70 degrees F. Monitor the soil to make sure it remains evenly moist. Mist the soil with water as needed.
Sow seeds directly in the garden bed in warm growing zones that have a soil temperature of 70 degrees F in early spring. Sprinkle the seeds over the warm soil and lightly cover them with 1/8 inch soil. Mist the soil with water each day for 10 days to keep it evenly moist during the germination process.
Fertilize indoor and outdoor marigold seedlings with a water-soluble 15-15-15 fertilizer once they reach 1 inch in height. Follow package instructions based on the amount of soil in the germination container or garden bed.
Transplant indoor seeded marigold seedlings into 2-inch growing containers filled with a moist, well-draining soil once the plants have a minimum of three true leaves. Place the containers in full sunlight and provide water to keep the soil evenly moist.
Transplant the indoor seeded marigolds to a garden bed or larger container once the seedlings reach a height of 4 inches and there is no longer a risk of frost. Fertilize marigold flowers only if the soil has a poor nutrient value. Marigolds produce flowers six to 12 weeks after seed germination.