News Release Distributed 08/13/10
By LSU AgCenter Horticulturists Dan Gill, Kyle Huffstickler and Allen Owings
Sunflowers are among the easiest flowers to grow, and they thrive in the heat of Louisiana summers. It may be towards the end of summer, but you can still plant sunflowers and enjoy them during the fall. In north Louisiana, try to complete sunflower planting by the third week in August. In central Louisiana, plant them by the end of the month, and south Louisiana gardeners can plant sunflowers through Labor Day.
Depending on the variety, sunflowers will bloom about 55 to 75 days after planting – 60 days is a good average. Sunflowers can be broadly divided into those grown for production of edible seeds and those grown as ornamentals and cut flowers. Most people are interested in the ornamental and cut flower types.
You can start sunflower seeds in small containers that have drainage holes and are filled with potting soil. Place the containers in full sun to produce strong, stocky transplants. Make sure you water them regularly and never allow the soil to become dry. When the seedlings have grown to be 4 to 6 inches high, transplant them to sunny flowerbeds.
You’ll get plants more quickly, however, if you directly sow seeds into a prepared garden bed in full sun. It’s common to plant sunflowers into landscape beds, and many gardeners include a row of sunflowers in spring and fall vegetable gardens. After sowing the seeds, water the bed well and then water it as needed to keep the soil moist – even lightly every day if the weather is dry.
Sunflowers come in heights ranging from 1-8 feet and also come in a wide range of flower colors. While brilliant yellow will always be popular, you can also choose from creamy white, bronze, mahogany, rusty red, burgundy and orange. Some types produce flowers with more than one color. The center disk of the sunflower also adds to the display and goes through color changes as the flower matures and seeds form. Some double types – such as Teddy Bear – produce flowers full of petals with no central disk at all. Ornamental varieties for cut flowers include Sunbeam and Sunbright.
Sunflowers grown for cut flowers generally produce numerous flowers on a more bushy plant than the types grown for seeds, which generally produce a single, large head. The multiple-flowering habit makes these types more colorful and helps them fit into traditional flowerbeds more appropriately.
If you want to grow sunflowers for the delicious, nutritious seeds, make sure you choose varieties bred for seed production, such as Mammoth Russian – also known as Mammoth, Russian Giant and Gray Stripe. These tall-growing sunflowers produce a single enormous flower at the top of the plant. To grow a really big seed head, apply general-purpose fertilizer when the flower head begins to appear.
The versatility and variety of today’s sunflowers offer something for almost every garden and gardener. If you haven’t tried this native American plant lately, give it another look.
Visit LaHouse in Baton Rouge to see sustainable landscape practices in action. The home and landscape resource center is near the intersection of Burbank Drive and Nicholson Drive (Louisiana Highway 30) in Baton Rouge, across the street from the LSU baseball stadium. For more information, go to www.louisianahouse.org and www.lsuagcenter.com/lyn.
Rick Bogren