Sunflowers add bright color to the garden. Whether you grow them for their edible seeds or as an ornamental plant, there are many varieties to choose from. There are dwarf types that reach less than 1 foot in height as well as towering giants of 6 feet or more. The flowers turn on their stems to face the sun as the plants require at least six hours of light a day. Sunflowers do not tolerate frost, so plant these seeds outdoors only after all frost danger has passed.
Spread 2 inches of mature compost over the planting bed. Work the compost into the top 6 inches of the soil, using a spade, to add nutrients and aid drainage in the soil.
Sow small sunflower varieties ½ inch deep and larger types 1 inch deep. Space seeds 6 inches apart in rows that are 1 to 2 feet apart.
Water the bed thoroughly after planting, moistening the top 6 inches of soil. Water again when the top 1 inch of soil begins to feel dry, maintaining the 6 inches of moisture in the bed.
Thin the seedlings after germination so they are 1 foot apart for small types and 2 to 3 feet apart for the larger types. The closer sunflowers are planted, the smaller the flowers are.
Spread a 2-inch layer of mulch around the sunflower plants once they are at least 6-inches tall. Organic mulches, such as bark chips, preserve soil moisture, prevent weeds and help maintain the warmth in the soil.