Blueberries are a group of flowering plants in the genus Vaccinium.
They are native to eastern Asia and North America. The leaves can be either deciduous or evergreen, oval shaped or lancelike. The flowers are bell-shaped, white, pale pink or red, sometimes tinged greenish.
The fruit is botanically a true berry about 15 mm diameter with a flared “crown” at the end; they are pale greenish at first, then reddish-purple, and finally turn blue or dark purple on ripening. They have a sweet taste when mature, with variable acidity. The blueberry season typically peaks in October and November here.
Source: Wikipedia