Growing Russian Giant Sunflowers

Choose a planting site that takes into consideration soil, shelter and sun direction. The soil should be fertile and well-draining, although you will have to keep it moist to produce lush, healthy sunflowers. If the site is not sheltered from the wind you will need stakes to support your growing flowers. Giant sunflowers are heliotropic, which means they will turn to face the sun, so plant them accordingly.

Plant groups of three to six Russian Giant sunflower seeds in small mounds of soil (about 6 to 8 inches apart) in an area that receives full sun for at least six to eight hours a day. Spring is the best time to plant, after all danger of frost.

Thin the flowers at several different growth stages to produce the healthiest crop. The first round consists of thinning your mounds to leave the healthiest seedling once sprouts emerge, typically five to 14 days after planting. Thin your sunflowers again when they reach heights of about 6 inches to leave the most vigorous, hearty growers, and again when they reach heights of 2 to 3 feet. The ideal end result for Russian Giant sunflowers is spacing about 18 to 22 inches apart.

Care for your sunflowers through the next months of their relatively short life cycle, which will only last about seven to nine months from planting to seed harvest. They die once they flower and produce seeds. They are tolerant of hot, dry weather, but will not survive extended droughts. As heavy feeders, they require regular feedings of a nitrogen-rich fertilizer, which promotes vegetative growth. Do not overfertilize, however, as this can produce bushy sunflowers with weak stems and small flowers.

Enjoy your mature Russian Giant sunflowers in bloom. They feature tall, single stalks that grow to heights between 10 and 15 feet topped by large flower faces with a diameter of 8 to 20 inches. These flower heads feature golden yellow ray petals and dozens of individual brown-colored florets. Each one of these flowers, if pollinated, will produce plump, thin-shelled grey-and-white-striped seeds in the fall that can be harvested for food.