Sunnyslope Greenhouse, 1621 Highway 163, Leighton, IA 50143, US

Established in 1952, Swift Greenhouses offers a range of plugs and potted plants to its customers. The company provides a variety of perennial and herb plants, including asparagus, hibiscus, campanula and lathyrus. The company features several species of plug tray seedlings, including Bellis perennis, Gazania linearis, Anchusa capensis and Dianthus caryophyllus. Its annual and vegetable plants include dahlias, eucalyptus, flowering cabbages and marigolds. Swift Greenhouses also sells potted ferns, grasses, mint and lilies. The company provides online catalogs and product ordering forms. It grows more than 1,300 varieties of plants in plugs and pots. Swift Greenhouses employs over 50 people and is located in Gilman, Iowa.