The sunflower (Helianthus annuus) is an annual plant with large flowers. Older varieties of sunflowers can grow as high as three metres, whilst newer varieties are often much shorter.
It is an important food crop worldwide and it is also a useful cut flower for the floral industry.[1]
The sunflower is native to North America.[1]
Description
Sunflower blooms are large and range in golden, yellow and orange colours. The sunflower is an inflorescence called a head.
The sunflower is formed by many hundreds of small, inconspicuous flowers formed close together.[1] Disk flowers form the center and these flowers each have male and female parts (namely, they are fertile).[1] The "petals" around the disk are ray flowers and have no reproductive parts, thus cannot form seeds (namely, they are infertile).[1] The ray flowers look like petals.
When the plant is young, the flowers turn to face the sun.[1] This ceases once the stem turns woody.[1]
Growing sunflowers
Sunflowers are a good garden plant and they're a great flower for children to grow when learning about gardening.
Choose seeds. The sunflower is happiest when sown directly where it is intended to grow it.
Choose a position that has full sun. The site must be sheltered from wind.
Choose a suitable soil. Sunflowers can tolerate both light and heavy soil, provided it drains well. However, the sunflower will grow best when the soil has plenty of organic matter and some fertiliser.
Sow seed in late spring or early summer, as long as the soil is warm. Be generous with the seeds, as you can thin out the seedlings once they take. Place 1cm/.5 inches of soil over the top of the seed once planted. If the seed is really large, cover with 2.5cm or 1 inch of soil.
Expect germination in about five to ten days. Keep the soil moist. Thin out the seedlings for best growth and large flowers. If the flowers are kept spaced close together, they form smaller and shorter flowers.
Caring for sunflowers
Water during dry weather.
Remove weeds to prevent the weeds competing with the sunflower plant.
If you remove spent flowers, the flowering will be prolonged, as is typical with many annuals.
Other than these basic care methods, sunflowers don't require much intervention whilst growing.
Uses for sunflowers
Sunflowers can be used for decorative purposes, in floral arrangement displays and on their own in a single vase.
The raw sunflower kernels can be eaten raw, or used in baking or cooking. They are a healthy snack to munch on. They are also excellent feed for birds and wildlife, and can be stockpiled to feed birds in your own garden during the colder months.
Sunflowers can be turned into sunflower oil. The stems can be turned into paper.
