People can't quite put a finger on what to make of the calamondin tree, or how to use its fruit-it doesn't look quite like a lime, not quite a true lemon, and it certainly does not taste like an orange. As a matter of fact, one bite of this fruit can pucker your mouth and curl your tongue. Read more . The small seedy fruit, with thin yellowish-green rind and soft, juicy flesh, is verrrry sour! If picked too soon, it is bitter! A good substitute in any lemon or lime recipe.