The Lois W. Poinier Collection documents the work of Lois W. Poinier, a self-taught garden designer who designed scores of gardens, most of them in New Jersey.

The Frederic H. Leubuscher Collection contains 106 duplicate 35mm slides documenting examples of Leubuscher's landscape architecture design work in New Jersey, New York, North Carolina, Rhode Island and other locations.

The Maida Babson Adams American Garden Collection documents the work of Molly Adams, a free-lance garden photographer who photographed hundreds of private and public gardens, many of them in the mid-Atlantic region, from the late 1950s through the mid-1990s. It includes slides, photographic prints, negatives and transparencies. A significant number of images document the work of landscape designers Nelva M. Weber, Alice Recknagel Ireys, and Friede Stege. Roughly 50 gardens do not have an identified location. Some images have captions and other information written on them.

The Roche Collection documents some of the work of John and Mary Alice Roche, garden photographers who photographed numerous gardens throughout the United States. Several of the Roches' images appeared in popular gardening magazines and books on flower arranging from the 1950s and 1960s.

The Corliss Knapp Engle slide collection contains 35mm slides of gardens, garden features, flower shows, and flora photographed by Corliss Engle, a self-taught photographer and horticulturalist. Much of the collection is comprised of photographic documentation of numerous private and public gardens that she visited throughout the United States. Of particular note are images of Engle's own garden in Brookline, Massachusetts, spanning three decades; they provide excellent insight into the development and evolution of a garden over time. Portions of the collection highlight Engle's involvement with the Garden Club of America and the GCA's Garden History and Design Committee. The collection also includes various notes, lecture scripts, brochures, programs and articles on garden and plant-related themes generated or compiled by Corliss Knapp Engle.

Collection consists of 183 35mm photographic slides that Dr. John M. Fogg took of a variety of arboreta, botanic gardens, plant nurseries, and other assorted gardens throughout the United States and Canada between 1955 and 1967.

The Bedman Brothers Company Records collection focuses primarily on the business and financial transactions of Bedman Brothers seed company of Rahway, New Jersey, and includes accounting ledgers, purchase orders, price lists, miscellaneous business and family correspondence, and various brochures, pamphlets and leaflets related to horticultural topics. Other holdings in the collection include World War II ration stamps and two scrapbooks, one of which contains many late nineteenth and early twentieth century chromo-lithographed trade cards (primarily from the sewing, clothing, and floral industries). The other scrapbook holds news clippings from the Civil War period. Seperated materials include seed gathering equipment used by field workers.

The American-Moninger Greenhouse Manufacturing Corporation Collection includes 306 architectural plans and drawings of greenhouses, solariums, conservatories, garages, and other structures designed by American-Moninger for clients throughout the United States dating from 1923 to 1964.

The Historic Gardens Postcard Collection includes 200 postcards of historic views of various public gardens, parks, monuments, and buildings throughout the United States and some foreign countries, including Canada, France and Cuba. Some private gardens and estates and many Washington, D.C. attractions are also represented. Roughly half of the postcards were mailed; the remaining postcards were not written on or posted. Areas represented include Arizona, California, Colorado, Delaware, Florida, Illinois, Indiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Nebraska, New Jersey, New York, Ohio, Oregon, Pennsylvania, Texas and Virginia. Foreign views show gardens in Havana, Paris, and Canada. About a dozen cards feature various views of Smithsonian Institution museums along the National Mall in Washington, D.C.

The Dr. G. Howard White, Jr. Collection contains images of family members and residences relating to the White family of Catonsville, Maryland and Middleburg, Virginia and the Liebig family of Catonsville, Maryland, as well as recreational, industrial, and general sites in Virginia, Maryland, and New Jersey. The images, taken by Dr. G. Howard White, Jr. and Dr. Gustav Adolph Liebig, both amateur photographers, document everything from informal family gatherings and outings to domestic servants, workers, factories and railroad lines. The acession file includes some genealogical information and research on properties conducted in 2005.