TITAN SUNFLOWER (Helianthus annuus), also known as Mammoth, is a monster in the garden - a Russian heirloom that produces mammoth yellow flower heads up to 24" across on stalks as tall as 12'. This is the one you grow to win a blue ribbon at the county fair! The seeds are also huge. 75 days. 50 seeds.
ABOUT SUNFLOWERS: Sunflowers in the bud stage exhibit heliotropism - which means they follow the sun. Give your kids a science lesson by showing them how at sunrise the faces of most sunflowers are turned East and over the course of the day that will ship to the West, returning at night to an eastward orientation. This motion is performed by motor cells in the pulvinus, a flexible segment of the stem just below the bud. At the bud stage ends, the stem stiffens and the blooming stage is reached. The sunflower is native to North America, and was used by early North American Indians for food and pressed to make hair oil. Meal from processed seed has been used for livestock feed. Today, whole seeds are used for oil, bird seed and snacks. The seeds are a rich source of calcium plus 11 other minerals. The 50 percent fat composition is mostly polyunsaturated linoleic acid. All sunflowers have the wonderful ability to clean toxins from the soil. Used by farmers converting to organic farming who need to clean old pesticides and chemical fertilizers from their soil, or by the Department of Energy, which owns most of the toxic sites here in the United States for "phytoremediation" - reclaiming toxic and radioactive environments.
GROWING TIP: If you are growing several varieties of sunflower, plan their location according to days to maturation and size so that they are able to display properly and/or be easily harvested. Fast growing, taller varieties can provide a wind and sun barrier, so keep that in mind if planting in the vegetable garden. Sunflowers will tolerate a wide range of soils, but do not use high nitrogen soil amendments, as it will check production of the flower heads. If growing for seed heads, give each plant plenty of room. Plant seeds 1-2" deep (no more than 3" deep) and at least a foot apart. I have noted that sunflowers started indoors do better, but it is not necessary. One critical chore for the home gardener is keeping weeds down in the first 4-5 weeks without disturbing the root structure. Hand weeding is best.