Sunflowers (Helianthus annus) are annuals reaching heights of 10 to 12 feet, depending on the variety. Sunflowers produce vibrant-colored 4-to-12-inch-wide flowers that are used for ornamental purposes and for obtaining edible sunflower seeds. Plant sunflowers in a sun-filled location in soil rich in organic matter.
Planting Sunflower Seeds
Fill up planting packs, or 2-to-3-inch-wide biodegradable pots with a quality seed starting mix. Plan on doing this in late March.
Pack the soil down in the planting packs or biodegradable pots until the soil is well firmed down.
Plant one sunflower seed in each of the cells, if using planting packs. If using biodegradable pots, plant two sunflower seeds into each of the pots.
Cover up the sunflower seeds with no more than 1/2 inch of the seed-raising mix. Mist the soil's surface using a spray bottle until the soil is visibly damp.
Put the planting packs, or biodegradable pots into a light-filled location that provides between eight and 10 hours of indirect light daily. Keep the soil on the damp side, but avoid letting it become drippy wet. The temperature should remain in the 60 to 65 degrees F range. Germination of sunflower seeds will occur in about eight to 10 days.
Transplant the sunflower seedlings to your garden when they are about 2 inches tall, in approximately middle to late May.
Choose a location in your garden that will provide the most sun. Sunflowers prefer growing in full sun, according to Floridata.com.
Prepare an area in your garden that is approximately 2 or 3 feet square. Remove all weeds, and their roots using a garden hoe.
Dig out the top 8-to-10-inch-deep layer of soil from the planting area. Mix into the soil you removed from the planting area 1 cubic foot of aged manure or dehydrated compost.
Remove another layer of soil, approximately 6 to 8 inches, from the planting area. Place this soil elsewhere in your garden. Fill the planting area with the soil and organic matter mixture.
Level and smooth out the soil in the planting area using a metal rake.
Dig planting holes for the sunflower seedlings that are between 12 and 16 inches apart. Each hole should be twice the diameter and approximately the same depth of either a cell in a planting pack or a biodegradable pot.
Pop out a sunflower seedling from a cell in the planting pack using your thumb and index finger. If using biodegradable pots, cut off the top section of the pot down to the soil line. Set the pots into a bowl of water to help soften the pot.
Set a sunflower seedling into one of the previously created planting holes. Scoop in soil in and around the seedling. Firm the soil down around the stem of the seedling. Water each of the sunflower seedlings with approximately 1 qt. of water.