The common names "sunflower" and "common sunflower" typically refer to
the popular annual species Helianthus annuus, whose round flower heads
in combination with the ligules look like the sun.
This and other species, notably Jerusalem artichoke (H. tuberosus), are cultivated in
temperate regions and some tropical regions as food crops for humans,
cattle, and poultry, and as ornamental plants. The species H. annuus
typically grows during the summer and into early fall, with the peak
growth season being mid-summer.
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