Confidence votes 35. Watermelons are thought to be indigious to Africa where they have been found growing wild. In the 1600s there were watermelon growers in Massachusetts and Florida. Watermelons can be grown almost anywhere but do best in humid areas.I have a freind in Montrael who grows watermelons.He uses black plastic on the ground to amplify the suns heat.n the 1600s there were watermelon growers in Massachusetts and Florida. Watermelons can be grown almost anywhere but do best in humid areas. I have a freind in Montrael who grows watermelons. He uses black plastic on the ground to amplify the suns heat.