From Lost Fables Wiki
Melons are watermelons. Except for being regarded as an excellent base for potions (in addition to smoothies) when emulsified, they are exactly like the melons you know and love.
Melons usually have a primarily dark green thick outer skin, with deep red, grainy but crisp and deliciously sweet watery flesh inside.
Watermelons have small yellow flowers which sprout occasionally from their vines.
Other than being delicious, they are an excellent base for potions, taking to other ingredients very well.