By: Justin Butts By: Rachel Benavides
Sunflowers are native to the Americas. Native Americans have cultivated them for more than 5,000 years – the Incas and Aztecs used sunflowers extensively in religious ceremonies, and tribes from Canada to South America harvested them for food, medicine, and dye.
After Cortez sent some home to Spain, the flowers grew in popularity throughout Europe, but it was in Russia where sunflower production exploded. Peter the Great spearheaded the movement, and by the 1800s, Russia was the leading global producer of sunflower seeds and sunflower oil.
The Russians bred an amazing array of sunflower varieties, some still considered among the best in the world, such as the popular “Russian mammoth.” By the 1960s, production took root in the United States on an industrial scale. Today, sunflowers are grown by vast commercial farms on the same land where Native Americans cultivated them on a small scale for centuries.
Sunflowers grow very tall. The shorter varieties rise to three feet, but the tallest – such as the “silver leaf” variety, which is native to the Coastal Bend – grow to a towering 18 feet in height. Sunflowers are not suitable for pots. They are also not best planted in small gardens, where they can quickly dominate and shade out other plants.
They do make a great summer windscreen for gardens. Native Americans frequently planted them in hedgerows on the windward side of their Three Sister gardens to protect more delicate vegetables from the wind. Sunflowers are powerful attractors of birds, bees, and other friends of the garden. They also absorb huge amounts of water; a sunflower hedge can slow runoff during the rainy season by holding the water in their thick stalks.
At the end of the season, cut all sunflowers at the base of the stem and burn them – their ash is one of the best fertilizers for the garden. Or, line the base of a compost pile with sunflowers, where the lignum-rich stalks will vitally enhance the finished compost.
Spacing, 12” to 18”. Height, 3’ to 20’. Grow any preferred varieties. Full sun. Plant March through July by seed in well-drained soil. Add compost and pastured poultry manure. Water until established and then weekly or as needed. To form hedgerow, till soil in desired location 3’ wide and as long as needed, then broadcast seeds by hand (can walk on bed to stamp into soil) and water deeply. No thinning required. No pests.
Sunflowers are too big for small, orderly gardens. Plant sunflowers any place tall, vigorous flowers will add vibrancy to the landscape. Plant as a seasonal hedge or summer shade for more delicate garden flowers. Clip sunflowers when the massive heads begin droop and look down. Hang flowers upside-down in paper bags in a cool, dry place until seeds fall to the bottom. Store seeds in freezer until ready to use.
Sunflowers are used to make rope, paper, and even latex. Sunflowers are also hyperaccumulators, which means they can draw large amounts of toxic chemicals from the soil. Planting sunflowers, then removing and safely burning the mature stalks, can help cleanse poisoned soils. They can also help reclaim marshes due to their ability to draw water from soil; they are planted extensively in the Netherlands to help convert marshes into arable land.