Watermelon (Citrullus lanatus) is a flowering plant species of the Cucurbitaceae family and the name of its edible fruit.

Watermelon is grown in favorable climates from tropical to temperate regions worldwide for its large edible fruit, which is a berry with a hard rind and no internal divisions, and is botanically called a pepo.

The sweet, juicy flesh is usually deep red to pink, with many black seeds, although seedless varieties exist.

[2] Wild watermelon seeds were found in Uan Muhuggiag, a prehistoric site in Libya that dates to approximately 3500 BC.

[4] Watermelons were domesticated in north-east Africa and cultivated in Egypt by 2000 BC, although they were not the sweet modern variety.

[citation needed] The large fruit is a kind of modified berry called a pepo with a thick rind (exocarp) and fleshy center (mesocarp and endocarp).

[8][9] A bitter watermelon, C. amarus, has become naturalized in semiarid regions of several continents, and is designated as a "pest plant" in parts of Western Australia where they are called "pig melon".

[13] Molecular data, including sequences from the original collection of Thunberg and other relevant type material, show that the sweet watermelon (Citrullus vulgaris Schrad.)

[17] The bitter wooly melon was formally described by Carl Peter Thunberg in 1794 and given the name Momordica lanata.

[20] Watermelon seeds were found in the Dead Sea region at the ancient settlements of Bab edh-Dhra and Tel Arad.

[21] Many 5000-year-old wild watermelon seeds (C. lanatus) were discovered at Uan Muhuggiag, a prehistoric archaeological site located in southwestern Libya.

It spread northwards through southern Europe, perhaps limited in its advance by summer temperatures being insufficient for good yields.

The fruit had begun appearing in European herbals by 1600, and was widely planted in Europe in the 17th century as a minor garden crop.

The modern watermelon, which tastes sweeter and is easier to open, was developed over time through selective breeding.

Watermelons were rapidly accepted in Hawaii and other Pacific islands when they were introduced there by explorers such as Captain James Cook.

[8] In the Civil War era United States, watermelons were commonly grown by free black people and became one symbol for the abolition of slavery.

The sentiment evolved into a racist stereotype where black people shared a supposed voracious appetite for watermelon, a fruit long associated with laziness and uncleanliness.

[2] The kordofan melon shares with the domestic watermelon loss of the bitterness gene while maintaining a sweet taste, unlike other wild African varieties from other regions, indicating a common origin, possibly cultivated in the Nile Valley by 2340 BC.

[29] In a 100-gram (3+1⁄2-ounce) serving, watermelon fruit supplies 125 kilojoules (30 kilocalories) of food energy and low amounts of essential nutrients (see table).

The more than 1,200[36] cultivars of watermelon range in weight from less than 1 kilogram (2+1⁄4 pounds) to more than 90 kg (200 lb); the flesh can be red, pink, orange, yellow or white.

[37] Charles Fredrick Andrus, a horticulturist at the USDA Vegetable Breeding Laboratory in Charleston, South Carolina, set out to produce a disease-resistant and wilt-resistant watermelon.

These are no longer grown to any great extent, but their lineage has been further developed into hybrid varieties with higher yields, better flesh quality and attractive appearance.

[9] The fruits are used by the San people and wild animals for both water and nourishment, allowing survival on a diet of tsamma for six weeks.

[9] The watermelon is used variously as a symbol of Palestinian resistance,[57][58][59] of the Kherson region in Ukraine, and of eco-socialism, as in 'green on the outside, red on the inside'.

[62] Watermelons are plants grown from tropical to temperate climates, needing temperatures higher than about 25 °C (77 °F) to thrive.

[8] The US Department of Agriculture recommends using at least one beehive per acre (4,000 m2 per hive) for pollination of conventional, seeded varieties for commercial plantings.

Watermelons have a longer growing period than other melons and can often take 85 days or more from the time of transplanting for the fruit to mature.

[37] Lack of pollen is thought to contribute to "hollow heart" which causes the flesh of the watermelon to develop a large hole, sometimes in an intricate, symmetric shape.

[67] The cubic shape was originally designed to make the melons easier to stack and store, but these "square watermelons" may be triple the price of normal ones, so appeal mainly to wealthy urban consumers.

[6] Secondary producers included Turkey, India, Iran, Algeria and Brazil – all having annual production of 2–3 million tonnes in 2020.