Summer officially arrived this week, and though this spring has been very gentle and (mostly) not-too-hot, we know without a doubt that the hot, heavy days are just around the corner. Yet while we moan and groan about the oppressive heat, the watermelon remains unfazed. It just loves the heat, a throwback to its origins in the southern part of the African continent, the Kalahari Desert. In the scorching desert, the watermelon, boasting a more-than-90% water content, was an important and vital source of liquid to humankind and wild animals. The difficulty in choosing a good watermelon is an old story. Even in its wild form, the sweet watermelon is identical on the outside to a bitter watermelon, necessitating the thirsty passerby to punch a hole in the watermelon rind to test its taste.