Florida is far from most of the nation's population centers, and its soils are generally low in fertility. Its only physical advantage is a relatively freeze-free winter. Winter and spring vegetables produced in Florida are marketed primarily in states east of the Mississippi River. Florida's share of the nation's production of several vegetables exceeds 70 percent. Heat and competition from northern vegetable areas preclude a summer vegetable season. The major areas of vegetable production are in south Florida, where freezes are least frequent, but where vegetable production competes with nursery plant and sugarcane production, as well as urban development. The largest vegetable region is the Mucklands, an area of rich organic soils south of Lake Okeechobee. To its east is the AtlanticÊbeachÊridge, where vegetables continue to be grown despite urban encroachment. The oldest south Florida growing area is in southern Dade County where in some places soil was created by pulverizing exposed bedrock. The newest large south Florida vegetable growing area is around Immokalee. In central Florida vegetables are grown in early spring around Wauchula, Plant City, and Sanford. Significant late spring vegetable production occurs farther north, particularly in Gadsden County.