Greenhouse Complex, Queens County Farm Museum

According to the museum, the Greenhouse Complex began in 1929 as a wood-frame potting shed. The farm then belonged to Creedmoor State Hospital, which used it for occupational therapy, to supply its kitchens and to grow ornamental plants for the rest of the campus; Wikipedia dates the hospital's purchase of the farm to 1926. The East and West Houses were built by the King Construction Company of North Tonawanda; the South House, raised in 1934 when Creedmoor wanted to expand the complex, was built by the Metropolitan Greenhouse Company of Brooklyn. A contractor on the restoration places the original construction "about 100 years" ago, with a renovation in the 1930s, but says it was told so: that second-hand account does not match the museum's 1929 date exactly.

Long abandoned and vandalised, the complex was taken over by the museum in 1975. The museum describes nine years of negotiations with the city's Department of Parks over a historically faithful restoration, followed by a refit that gave up some historical accuracy; the greenhouses were open to the public by 1997. The next project, run by the city's Department of Design and Construction (DDC), began in October 2015 at a cost of 2.4 million dollars and was due to finish in late spring 2017. Conservatory Craftsmen, hired by the city in early 2014, recalls that by 2016 the roof glass was falling out of rotted wooden frames.

The three greenhouses are glass-covered structures on wooden frames, set on concrete walls. The restoration carried out from 2015 by the DDC, with John G. Waite Architects and Conservatory Craftsmen as designers and NSP Enterprises of Brooklyn as general contractor, replaced the framing and the historic venting hardware. For the new frame the DDC cites Accoya acetylated wood, described as non-corrosive, waterproof and termite-proof, while the concrete walls were patched and repainted with the historic elements protected.

The sloped roof now carries 5/16-inch (about 8 mm) laminated, heat-strengthened glass, with stainless-steel interior gutters that collect moisture from the underside of the glass. Conservatory Craftsmen explains that the original glass was thin annealed float glass, dangerous when it broke, whereas today's glass is tempered and laminated. The roof and side vents are still worked by hand through gears and levers: a modern greenhouse would automate them, but the restoration kept the original operation, and farm staff open and close them themselves.

The Greenhouse Complex is a production greenhouse rather than a botanical collection. The museum starts all of its crop seeds there: an on-site greenhouse lets it keep the whole production cycle in one place and spares it from trucking in young plants. According to its 2025 presentation, the South and West Houses are used for seeding and germinating plants for the fields, while the East House sells seasonal plants and seedlings.

The Farm Store carries seasonal plants from spring through autumn, and its May plant sale features vegetable seedlings propagated at the farm using organic methods. In the days of Creedmoor hospital the farm already raised ornamental plants for the campus, according to Wikipedia.

The complex stands at the heart of the farm museum in Glen Oaks, at 73-50 Little Neck Parkway in Queens. For visitors the way in is the central section, which serves as the farm's welcome centre and shop (Welcome Center and Farm Store); the East House sells seasonal plants, whereas the South and West Houses are used for production.

The farm, which the city describes as the only working historical farm in New York City, covers 47 acres (about 19 ha). A visit to the greenhouses can be combined with the Adriance Farmhouse, built in 1772, the fields, the orchard, the herb garden, the apiary and the animals. Each May the museum holds a vegetable plant sale and a sheep-shearing festival, two occasions to see the farm in full swing.