Unless you grew up eating it, fu gwa (also known as bitter melon, bitter gourd, kerala or balsam pear) can be quite unpalatable. It's bitter, as the name would indicate, and the wrinkled, warty skin is unappealing.
When is it in season? It's available year-round, but is considered best from spring through early autumn.
Where is it eaten? It's popular in Chinese, Indian and some Southeast Asian cuisines. It's grown in other countries but more for the plant's ornamental value than as a food.
Varieties: the types most often found in local markets are pale to dark green with wrinkled skin, and are either short and stubby or long and thin. There are also miniature varieties, white bitter melon and some that have spikes and/or bumps rather than wrinkles.
How to choose: they should be firm with no soft or discoloured spots. Pale green or yellow-green melons are milder than the darker green ones.
What else? Bitter melons are filled with inedible seeds and pith, which ranges from creamy white to pale green to light orangy-pink. These need to be removed before cooking the melon.