Hello Gardeners, I’m Amanda McNulty with Clemson Extension and Making It Grow . From its beginning as a modest fishing pond, Swan Lake Iris Gardens, in the heart of Sumter, now encompasses property donated in the thirties by A. T. Heath. Graceful swans add to the serene nature of this cypress-lined black-water lake with its displays of camellias and azaleas and magnolia trees. But in May, thousands of visitors come to see the stunning blooms of Japanese iris growing throughout the garden.