The Conservatory of Flowers is a greenhouse and botanical garden that houses a collection of rare and exotic plants in Golden Gate Park, San Francisco, California. With construction having been completed in 1879, it is the oldest building in the park. It was one of the first municipal conservatories constructed in the United States and is the oldest remaining municipal wooden conservatory in the country. For these distinctions and for its associated historical, architectural, and engineering merits, the Conservatory of Flowers is listed on the National Register of Historic Places and the California Register of Historical Places. It is a California Historical Landmark and a San Francisco Designated Landmark.
The Conservatory of Flowers is now one of the three locations of the Gardens of Golden Gate Park, along with the Japanese Tea Garden and the San Francisco Botanical Garden.
Architectural description
The Conservatory of Flowers is an elaborate Victorian greenhouse with a central dome rising nearly high and arch-shaped wings extending from it for an overall length of . The building sits atop a gentle slope overlooking Conservatory Valley. The structural members are articulated through one predominant form, a four-centered or Tudor arch.
The Conservatory of Flowers consists of a wood structural skeleton with glass walls set on a raised masonry foundation. The entire structure has a shallow E-shaped plan that is oriented along an east–west axis. The central high pavilion is entered through a one-story, glassed-in vestibule with a gable roof on the south side of the pavilion. Flanking the rotunda to the east and west are one-story, symmetrical wings framed by wood arches. Each wing is L-shaped in plan, with cupolas adorning the intersection of the two segments.
The octagonal pavilion supports an arched roof that is, in turn, surmounted by a clerestory and dome. The clerestory is supported by eight free-standing, wood-clad, cast-iron columns located within the rotunda and grouped in pairs. Projecting from the pavilion roof on the east, west, and south elevations are dormer windows with peak roofs. Between major arched structural framing members are wood muntins that hold the glass lights on their sides. The lights lap one over one another like shingles and follow the curve of the arches.
The construction of each arch is aesthetically appealing in its simplicity, but also structurally clever in that it takes maximum advantage of wood as a building material while overcoming its inherent structural shortcomings. From a structural perspective, the arch design uses the mechanical properties of the material. Wood is strongest along the length of the grain and weakest along the end grain. The use of short arch components with shallow radii minimized the amount of weaker-end grain exposed to structural forces. The assembly of the arch with several small pieces of wood, the shapes of which are identical from arch to arch, was efficient. It allowed the fabricator to set machines with guides and templates so that cutting the multiple-arch components was a simple task. Furthermore, the design required little material, since each individual arch component has only a shallow radius. Moreover, by using relatively narrow widths of lumber, the chance of warping was minimized. Finally, there was an efficiency realized in transportation, as the small size of the arch components allowed them to be easily stored and shipped.
The structural wood arches and their method of construction, along with the decorative woodwork and unique lapped glazing, define the character of the conservatory. The major character-defining elements consist of ornamental and structural woodwork, including the method of fabrication used for the arches, the lapped glazing system, the ventilation system, and the building's siting and exterior landscaping.An extensive architectural description and building history is located in the Conservatory of Flowers Complex in Golden Gate Park: Historic Structures Report, prepared for the San Francisco Recreation & Parks Department by Architectural Resources Group in 1998. The project historian was M. Bridget Maley, M.A., and the principal-in-charge was Bruce Judd, FAIA.
Rooms within the conservatory
Potted Plants Gallery: The Potted Plant room holds various unusual plants. The pots and urns that hold the plants were created by various artists from around the world. This room is maintained at hotter temperatures to accommodate the needs of the plants. The Potted Plant Gallery follows Victorian architecture and the 19th century idea of displaying tropical plants in non-tropical parts of the world. Lowlands Gallery: The Lowlands Gallery contains plants from the tropics of South America (near the equator). This room also contains plants that produce more well-known products such as bananas, coffee, and cinnamon. The room is usually kept around 70 °F with a very high level of humidity through the use of a frequent system of misters, as the Lowland Tropics typically get 100–400 inches of rain each year and are located in elevations from 3,000 feet to sea level. Highlands Gallery: The Highlands Gallery contains native plants from South to Central America. Its plants collect moisture from the air, and from water that drips from the trees above. Due to its drastically higher elevation (3,000–10,000 feet), this room is kept cooler than the Lowlands Gallery (around 65 °F) and is kept at a very high level of humidity through the use of a misting system, as the Highland Tropics typically receive 200 inches of rain per year. Aquatics Gallery: The Aquatic Plants room is similar in conditions as those near the Amazon River. As such, many carnivorous plants that thrive in hot, humid environments grow throughout the room. The soil is mostly lacking in nutrients and the carnivorous plants are kept very moist by condensation of the water in the extremely humid air. The room also contains two large ponds, one holding 9,000 gallons of water, and the other holding half as much. Both ponds are kept at 83 °F and are maintained using beneficial bacteria, filters, water heaters, and solutions to prevent algae buildup.
History and construction Historical context In both Europe and America, the 19th century brought increased urbanization and industrialization. In response, city governments began providing open spaces and natural settings for public use.Several studies have been undertaken concerning the development of the urban park in America, including John Reps, The Making of Urban America, 1965; David Schuyler, The New Urban Landscape: The Redefinition of City Form in Nineteenth Century America; and Galen Cranz, The Politics of Park Design, 1982. The profession of Landscape Architecture expanded during the later part of the 19th century, and park design became a large part of this new profession's repertoire. In addition, a significant outgrowth of the need for natural surroundings in urban contexts was an increase in the study of plant sciences during this period, both by professionals and amateurs. A building type called the glasshouse or conservatory took shape, in which the city-dweller could view masterpieces of the plant world otherwise unavailable in urban environments. Municipalities and individuals spent a great deal of time and money to construct these building types, which became known as "theaters of nature."
The 19th-century glasshouse grew out of the city-dweller's desire to bring nature and the natural into urban life.An extensive study of the glasshouse building type is Georg Kohlmaier and Barna von Sartory's Houses of Glass: A Nineteenth-Century Building Type, 1996, which focuses primarily on European structures. A second source that discusses American structures is May Woods and Arete Swartz Warren's Glass Houses: A History of Greenhouses, Orangeries and Conservatories, 1988. These structures became popular in urban, public, and semi-public settings. As these structures gained popularity in Europe, greenhouses began to be constructed on larger scales and of stronger materials. One engineer, Joseph Paxton (1803–1865), had an enormous effect on the development of the conservatory building type. His structures called for a system of glass and metal roof construction, whereas past structures had typically been constructed of wood and glass. His choice of materials allowed designs for glasshouses of substantially larger scales. His best known example is the Crystal Palace at the world's first International Exhibition in 1851. Elsewhere in Europe, Hector Horeau designed several conservatories of glass and iron, such as the Lyons Conservatory in France of 1847. In Germany, August von Voit designed the Great Palm House in the Old Botanical Gardens in Munich in 1860. Another prominent example is the Palm House in the Royal Botanic Gardens, Kew in London.
The increased use of glass and iron as building materials also impacted the development of the glasshouse. The decades following the construction of the Crystal Palace saw a decline in the use of wood structural members for the construction of large European greenhouses or conservatories. Many manufacturers had found that the humid heat necessary to successfully propagate numerous plant varieties often destroyed wood structural members in short periods of time.Kohlmaier, George and Von Sartory, Barna (1996) Houses of Glass
Following European fashions, wealthy Americans began to construct conservatories in the mid-19th century on private estates.
These structures were enjoyed by a broad cross-section of the public and were popular throughout California's early history. Structures of various shapes and sizes were built in Victorian California, ranging from an attached and glassed-in wing for a residence, to a great domed or compartmentalized, detached glasshouse.Richey, Elinor (1970) The Ultimate Victorians of the Continental Side of San Francisco Bay Examples of wealthy Californians who built conservatories in their private estates include: A.K.P. (Albion Keith Paris) Harmon, for his Oakland Lake Merritt Estate (which later became Lakeside Park); Frederick Delger; Frank M. Smith; Darius Ogden Mills (Millbrae); and Luther Burbank, for his own experiments with plant germination (Santa Rosa). These examples all used wood as structural members.Wessel, David and Cocks, James (2007) "Repairing Victorian Wooden Greenhouses of the West Coast" presented at the annual meeting of the American Institute for Conservation
The conservatory
The material for two conservatories modeled after Kew Gardens in London was originally bought in 1876 by James Lick, an eccentric businessman, piano maker, and successful real estate investor who was a patron of the sciences. It is believed that Lick purchased the materials from Lord & Burnham, a manufacturer of greenhouses located in upstate New York, and these were sent in kit form, to be assembled on site. The order is said to have been the company's first big sale. The 33 tons of glass were sent by boat – most probably one chartered by Lick – from New York, around Cape Horn to San Francisco Bay.