Lakeland Highlands is an unincorporated community and census-designated place in Polk County, Florida, United States. The population was 11,056 at the 2010 census. It is part of the Lakeland–Winter Haven Metropolitan Statistical Area. It is an affluent residential community located south of the Lakeland city limits, and north of the Mulberry city limits. …Lakeland Highlands is an unincorporated community and census-designated place in Polk County, Florida, United States. The population was 11,056 at the 2010 census. It is part of the Lakeland–Winter Haven Metropolitan Statistical Area. It is an affluent residential community located south of the Lakeland city limits, and north of the Mulberry city limits. Lakeland Highlands neighbors Medulla, and together the two communities make up much of what is known as South Lakeland.