Early watermelons were bitter, pale and grown mainly as portable water
The first watermelons were not the sweet red slices of today. Their pale, bitter flesh was hard to open, and people valued them for storing water through the dry season. In the Kalahari and East Africa, people and animals still rely on them for water, while centuries of breeding produced the sugary fruit sold everywhere else.
The crop was domesticated in Sudan, and the Kordofan melon found there is its closest known relative. The two share a lost bitterness gene, pointing to a common origin, possibly in the Nile Valley by 2340 BC. Wild seeds roughly 5,000 years old turned up at Uan Muhuggiag in the Libyan desert, and Egyptians were growing the plant by 2000 BC. It reached India by the seventh century and China by the tenth, and the Moors brought it to Córdoba, where it was grown in 961.
Botanists spent decades mislabelling it. Linnaeus described the sweet watermelon in 1753, but in 1930 L. H. Bailey wrongly merged it with a bitter woolly melon, so the edible fruit ended up under the wrong species name. DNA from the original specimens showed the two are only distantly related, and in 2017 a botanical congress kept the name Citrullus lanatus by special ruling anyway. The closest wild relative now appears to be a West African species found from Senegal to Nigeria.
The vine trails up to 3 metres, and each plant carries separate male and female flowers. A normal fruit needs about a thousand pollen grains spread evenly across the stigma's three lobes. Seedless triploid melons, first bred in Japan in 1939, carry sterile pollen, so growers plant rows of seeded varieties alongside and triple the number of beehives. By 2014 seedless types made up nearly 85 percent of watermelon sales in the United States.
The fruit is 91 percent water, and there are more than 1,200 varieties. The heaviest on record, a Carolina Cross, weighed 159 kilograms. China grew 60 percent of the world's 105 million tonnes in 2024.
Source: Watermelon
