Marigold, or calendula officinalis, is commonly referred to as English marigold, pot marigold, calendula and golds. Native to areas in Southern Europe near the Mediterranean Sea, marigolds produce beautiful blooms in an array of bright, sunny colors that last from summer to fall in cool regions of the country. Marigolds are spaced according to whether you are planting seeds or transplants and in relation to the expected width of the specific variety.
Marigolds can range in size from 12 to 30 inches in both height and width. This varies, depending on the specific marigold variety. The plant produces vivid green leaves around 4 inches long and single or double, daisy-like flowers on broad, stout stems six to seven weeks after planting. The marigold flowers vary from light pastel hues to bright yellows and oranges with identical or contrasting centers. Some cultivars are bicolor.
Planting Seeds Indoors
Grow your own transplants by planting marigold seeds indoors six to eight weeks before the last expected frost. Use seed trays with drainage holes and top-quality potting soil. Dampen the soil and sow the seeds as directed on the seed packet, or about a quarter-inch deep. Sow two seeds every 2 to 3 inches in trays without individual cells or two seeds in each cell. Place the tray in a warm location and keep the soil moist until the seedlings emerge in a week or more.
Seedling Care and Transplanting
Thin marigold seedlings to one plant per cell or one every 3 inches when they reach 3 inches tall. Maintain moist soil until the seedlings are transplanted outside in the landscape. Wait until after the chance of frost has passed to move the plants outside or to plant any marigold transplants. Dig holes the same depth of the containers and twice the width. Space the transplants from 9 to 18 inches apart or equal to about half the expected width of the specific marigold variety grown.
Direct Sowing and Thinning
Sow the marigold seeds directly outside just before the last frost. Select a planting location with well-draining soil and full to partial sun. In areas with extremely hot summers, select locations with afternoon shade. Dampen the soil and sow two seeds an eighth- to quarter-inch deep every 6 inches. Water the area as needed to maintain moist soil. Thin marigold seedlings planted outside to a spacing of one plant every 12 to 18 inches or at a spacing equal to about half of the plants' expected width.