It is currently unknown how or why the watermelon, or "melon" has spread so profusely across the Combine-controlled globe, how it finds its way into cities without detection, or if any other fruits and vegetables have avoided extinction following the Portal Storms and the mass extinction of Earth's life forms following the spread of Xen creatures. What is known, however, is that Melons are found almost universally and can be rather easily located in Combine-controlled cities. This is subject to interest, as many location, such as City 17 and City 45 in the former nation of Russia, have climates that were unsuitable to the growth of crops even before the Combine invasion.
As contraband, having a Melon in one's possession is grounds for punishment by the MPF, with severity depending on that particular city's codes concerning illegal consumables. They are, however, greatly appreciated by the Resistance, who make heavy use of Melons and other edible contraband in order to avoid Universal Union-produced food and drink, which often has memory-altering chemicals within it.
To consume a melon, the player must select it by clicking on it in inventory or pressing the action key (default "E") when looking at it. The option "eat" must then be selected, at which point a chewing sound will be heard and a small bit of health will be restored.