The tree of the sweet orange often reaches 6 metres (20 feet) in height. The broad, glossy, evergreen leaves
are
medium-sized and ovate; the petioles (leafstalks) have narrow wings. Its white five-petaled flowers are very
fragrant.
The fruit is a modified berry known as a hesperidium, and the flesh is divided into segments called carpels.
The
usual
shape of the sweet-orange fruit is round and the colour of its pulp orange, but there are variations. The
mandarin, for
example, is distinctly flattened, and the blood orange has red pulp. The pulp of the sweet orange is
agreeably
acidulous
and sweet; the leathery peel is comparatively smooth; and the oil glands are convex. Oranges are picked when
fully ripe,
for, unlike some deciduous fruits, they do not ripen or improve in quality after being picked. The trees
bear
abundantly
from 50 to 80 years or even more, and some old orange trees whose age must be reckoned by centuries still
produce crops.