Sunflowers are captivating flowers. They are the topic of multi-million dollar art, the desire of small children looking for a snack, and fun addition to a garden. Homesteaders and livestock owners love sunflowers seeds for feed; dehulled sunflower seeds are 41% protein.*
Sunflowers are novice plants. There are many things you can do to encourage growth and a successful crop. However, sunflowers will grow under less than desirable circumstances.*
Before You Start
Choosing to grow sunflowers for seeds is understandable. Russian and Mammoth sunflowers are ideal genus for seed production. Please realize if you live in a short growing season area (like Wyoming) you will have to transplant or use a low tunnel to extend your growing season. Also, sunflowers do not do well in swampy areas. Raised bed or furrows maybe required for badly draining areas.
Growing for Flowers
There are 69 different varieties of sunflowers. Teddy Bear has a unique flower and only reach 2-3 feet tall. Henry Wildes are traditional, a good cut flower and perfect for short growing seasons. The best choice for you will come down to personal taste and zone. There are heat and cold tolerant varieties. Also, keep in mind some genus need pollinators; like bees.
What Fire Blossom Farm Grows
Sunflower, Mammoth Gray Stripe*
Grow 9-12 ft tall. Flowers are 1’ across
Heirloom variety with no patent
How We Grow Sunflowers
Let me preface this by this is easier than you think. And we do a lot of extra work to make sure our plants survive. Fire Blossom Farm has a huge 72 day growing season. Our two plots are zone 4B and 5A. We start seed and grow inside for 3 weeks. 4″ round topsoil is used to make a newspaper plug. Once the seed hull is used up, a small amount of fertilizer is added to the flowers waterings. The next week the plants are hardened off. Then we transplant 3-4 weeks before the last frost in a taller-low tunnel.
Prepare bed, loosen soil 2’ down as sunflowers’ roots tap deep. Germination is 7-14 days, depending genus. After danger of frost has passed, sow ½ inch deep, 6” apart, in 2’ rows. Soil temperature should be 55-60 degrees F. Thin to 18” apart after plants reach 3”-4”.* (Sunflowers can have a low germination rate.)
Sunflowers are high water demand. However, encourage root growth by not watering too often or sunflowers will grow too fast, ripping themselves out of the soil. Water extra only during warm weather to avoid wilting. Soil should stay moist. However, in colder weather, if the soil is too moist, and the sunniest of flowers become susceptible to fungal infections.
Rotate crop every 3-4 years.* Sunflowers need rich well-drained soil. Soil should have aged manure, compost, or granulated fertilizer worked 8” down. Sunflowers have a pH requirement of 6.0 to 7.5.*
Protect from the wind. May need to stake some variety. Don’t let weeds choke sunflowers out, especial the first 8 weeks of growing.
Yields on sunflowers per square foot, according to the Jeffersonian Institute, is approximately .04 pounds of seed per square foot.* San Angelo Texas, Agrilife Research and Extension Center’s estimates yields at .032 pounds per square foot. Purdue in Indiana, suggested that hybrids have increased seed production but their estimated average was even lower at .031 pound per square foot.*
Damage by birds will outstrip rust infection, moths, and drought. According to National Sunflower Association 15% of a crop can be lost to birds.* Tape paper bag or breathable fabric over seed head to protect from birds.
Weeds interfering with nutrients and early development can stunt a sunflower seed crop by 11%.* Use fabric with 6”-8” holes for each flower. This suppresses weeds and keeps water in.
Harvest & Cure
It is 100 days to maturity for Mammoths.* Flowers are usually ready 30-45 days after flower blossoms. You can harvest when the foliage connecting the flower, and stalk turns brown. Cut head of sunflower off the stalk, leave 1’ of stalk attached. Drag sunflower head over mesh screen to collect seeds. Keep seeds dry until ready for use.
Sunflowers have the highest levels of phytosterols. Phytosterols lower cholesterol and increase heart health. The seeds are also an excellent source of fat and protein. They also lack the compounds that cause higher cases of allergic reaction. So if you are allergic to most nuts you may not be allergic to sunflowers. Facts provided by Topsoil Fair Education Department.*
Sources: sited with *