Giant Sunflower
The Giant Sunflower Can Grow to be Over 20 Feet Tall!
The giant sunflower or helianthus giganteus is a type of wild sunflower native to the Eastern United States and Southeastern Canada. It grows to over thirteen feet tall and the sunflowers are almost three inches across. This wild giant sunflower likes to grow in wet conditions and is usually seen in swamps and wet meadows. The flowers are a bright yellow.
The wild giant sunflower has been domesticated and cultivated so that there are now many kinds of hybrids available that grow very tall, and each one seems to rival the previous one in both plant and flower size. Colors now available in giant sunflower seeds include not only the traditional yellow, but also orange, orange-red, ruby red, apricot, burgundy and several bi-colored varieties.
Giant sunflower breeder Tom Heaton is credited with developing many of the largest plants that are being grown today. His American Giant Hybrid grows from fourteen to twenty-nine feet high and has a flower head that can be over two feet across. Other varieties of the giant sunflower that he has cultivated include Paul Bunyon--13 to 15 feet high with a 12-14 inch head, Kong Hybrid--14 feet high and multi-headed with 6-inch flowers, Sunzilla--12-14 feet high, and Cyclops Hybrid--15 feet high with a 12-14 inch flower head. All of these sunflowers are ideal for backyard gardeners.
Canadian Norm Craven’s hybrid sunflower can grow in excess of 25 feet high and have a flower head of 20+ inches. This remarkable plant has leaves that are two feet long and the stem can grow as thick as ten inches. This is the giant sunflower with the longest growing period--120 days. Marvin Hemker of St. Charles, MI holds the record for the most flowers on one giant sunflower, established when he grew a multi-headed sunflower in 2001 with 837 individual flowers. Hemker’s giant sunflower plant grows 8-11 feet high and 3-6 feet wide. It produces anywhere from 200 to the record-breaking 837 flowers.
Growing a giant sunflower hybrid takes much more care than growing an ordinary sunflower plant. The larger a sunflower, the more food it will feed on, so fertilizing giant sunflower plants is a must. Experts recommend slow release fertilizers that contain trace minerals but compost, manure, and organic fertilizers will also work well when applied judiciously. Nutrient-dense fertilizers such as Miracle-Gro ™ are also beneficial. Best results are also obtained when planting seeds directly into the soil and not starting the sunflowers inside. Allowing enough space between plants is another necessity.
With tender loving care, your giant sunflowers should grow quickly. Before harvesting, don’t forget to have a photo taken of you standing beside your 20-foot sunflower plant.