The calamondin (Citrofortunella mitis) is a fairly well-known citrus fruit in south Florida, where it is grown generally as an ornamental. Upon first meeting, most folks don't know exactly how to classify it. A little bigger than the size of your thumb nail, about 30mm in diameter, it has the inviting smell of tangerine with a very thin orange skin. You're tempted to peel it and pop the whole thing in your mouth, which would not be a good idea, for it is quite sour.

It originally came from the Philippines, but it now can be found from China and Java to Chile and Panama. It arrived in Florida in 1899 when it was first known as the acid orange and later as the Panama orange. Like many citrus, it is high in vitamin C and the juice is a very potent vitamin supplement.

Most owners of the calamondin have no idea what to do with it except to admire it. A native Floridian showed me that it could be frozen whole and used a ice cubes in beverages like sun tea and ginger ale. A good swat will crush the fruit, releasing the juice, which can be used to concoct another kind of lemonade. In Asia I understand it is used to baste fish, fowl and even pork.

My favorite, though, is calamondin marmalade, made in the same way as orange marmalade. It provides a powerful morning waker-upper on toast, if the system can handle so much stimulation that early in the day.