About those exploding watermelons

The sensational headline traveled around the world faster than green grass through a goose: 

Overdose of Growth Hormone Causes Exploding Watermelons in China! 

According to the BBC, the Associated Press and others, the obvious explanation for these bursting watermelons was an overdose of the growth accelerator Forchlorfenuron. An EPA bulletin says this chemical was released in 2004 for use on grapes and Kiwi fruit in this country. It is apparently so effective that its recommended rate of application is 2-8 grams per acre for Kiwis. 

Farmer Liu Mingsuo didn’t get the EPA bulletin however, and soaked his melons with the stuff. Before long they were going off “like land mines,” and 8 acres were ruined. About 20 farmers and 115 acres of melons were affected overall, but most hadn’t even used the chemical. 

Though melons in Shanghai markets show signs of the overuse of Forchlorfenuron, (“fibrous, misshapen fruits with mostly white, instead of black seeds”) it is doubtful that chemicals caused the melons to explode.  Growth hormones have been used on apples, citrus, tomatoes, and other fruits and vegetables since the 1930s with no known explosions. 

Horticultural professor Wang Liangju explained that the farmers were using a thin skinned variety of melons that are actually nicknamed “exploding melons,” because of their tendency to split open. In addition, he said the melons began “exploding” after a heavy rainfall. 

This is more common than one might think. After dry weather a heavy downpour can cause many fleshy fruits and vegetables to split open due to a rapid intake of moisture. Anyone who has picked a split tomato, radish or pepper has witnessed this. Nurserymen use this rapid moisture intake to their advantage by letting plants dry out slightly before giving them a weak solution of water soluble fertilizer. 

Uneven watering isn’t the only reason watermelons might explode; a librarian from Texas writes that when she cut into a watermelon 2 days after buying it, “It exploded! Seeds and pieces of that melon went in all directions, including on the white blouse I was wearing!” Many others have had this same experience after leaving watermelons in a warm place for awhile. 

According to the Alabama Extension System, Bacterial fruit blotch has caused watermelon explosions in one or more states on the eastern seaboard and in Alabama every year since 1989. This disease can cause melons to literally ferment inside their skins. “Effervescent exudates” (a fancy term for seeping, bubbling liquids) are often seen on the rind of affected fruit, and like an over-filled balloon they sometimes pop, especially when heated by the sun.

Finding a split watermelon or two doesn’t mean someone snuck into your garden and sprayed growth hormones, because it’s a very common occurrence. The Chinese horticulturalist’s explanation that a lot of rain and thin skinned fruit caused it on such a grand scale in China certainly seems the most plausible one.

Though inaccurate, maybe the headlines will get people thinking about what they are doing to their food and themselves when they use these chemicals. You have to wonder how much hope there is for China though; in March of last year authorities seized and destroyed 3.5 tons of 3 foot long beans (?) that had been treated with the banned pesticide isocarbophos.