Helianthus (Sunflower) is a genus comprising 52 species of flowering plants in family Asteraceae, native to North America.
Helianthus is an easy to grow, fast growing annual and perennial plant. It can grow to 1.5-3.5 m tall, produce a single, huge flower at the top of the sturdy stem. At sunrise, the faces of most sunflowers are turned towards the east. Over the course of the days, they follow the direction of the sun, from east to west. At night, they will return to an eastward orientation.
What is usually called the flower is actually a head of small flowers crowded together. The outer florets are the sterile ray florets that come in yellow, maroon, orange, or other colors. The florets inside the circular head are called disc florets, which mature into sunflower seeds, the fruit of the plant. The fruit is covered by an inedible husk and the true seed lies within the kernel.
Sunflower seeds (with husk) are sold as a snack food, after roasting in oven, with or without salt added. The seeds can also be processed into Sunbutter, a peanut butter alternative. It can be added to flour to make bread, sold as food for birds, or can be used directly in cooking and salads.
Sunflower oil (extracted from the seeds) is cheaper than olive oil, and is used for cooking, as a carrier oil and also to produce margarine and biodiesel.
Helianthus annuus (Sunflower) and Helianthus tuberosus ( Jerusalem artichoke) are cultivated as food crops and ornamental plants in Europe and other parts of the world. Helianthus is also good as cut flowers.
The sunflower is the state flower of the US State of Kansas, and the national flower of Ukraine. It is also subject of Van Gogh's most famous still life, Sunflowers (series of paintings).
Plant Helianthus in full sun, fertile, moisture-retentive but well-drained neutral to alkaline soil. Propagation is by seed and division in spring. Pests that affect the growth of the plant are slugs and snails.
http://commons.wikimedia.org/wiki/File:A_sunflower.jpg
Pamri
