The Botanical Garden originally featured 16 show greenhouses, 15 of which remain today, constructed on the southwestern slope of the Fichtenberg, allowing for an optimal layout and functionality. These greenhouses were designed to showcase specific plant collections in carefully controlled environments replicating their natural habitats.
Original greenhouse layout Fourteen of the remaining 15 greenhouses form a rectangular complex dominated by the Great Tropical Greenhouse. The layout takes advantage of the slope, with larger greenhouses positioned in the second row, higher up and smaller, flatter greenhouses situated three meters lower along the main path. This arrangement maximises sunlight exposure and prevents mutual shading. • A: The Great Tropical Greenhouse (reopened in September 2009 after extensive renovations) • B:
Begonias • C: Tropical Useful Plants • D:
Orchids and
Pitcher Plants • E: Plants of the Humid Tropics • F: Tropical and Subtropical
Ferns • G:
Bromeliads • H:
Succulent Plants of
Africa • I:
Cacti and Other
Succulent Plants of the
Americas • K:
South African Plants • L:
Carnivorous Plants and Plants of the
Southern Hemisphere • M: Plants from
Australia and
New Zealand • N:
Camellias and
Azaleas • O: Victoria House and Marsh Plant House (reopened after restoration) • P:
Mediterranean and
Canary Islands Plants
Back Row: •
C: Tropical Useful Plants (393 m2, 11.50 m height) •
M: Plants from Australia and New Zealand (393 m2, 11.50 m height) Connected by: •
B: Begonias (288 m2, 4.50 m height) •
N: Camellias and Azaleas (288 m2, 4.50 m height)
Front Row: •
E: Plants of the Humid Tropics (154 m2, 9.30 m height) •
G: Bromeliads (154 m2, 9.30 m height) •
H: Succulent Plants of Africa (154 m2, 9.30 m height) •
K: South African Plants (154 m2, 9.30 m height) Connected by: •
F: Tropical and Subtropical Ferns (191 m2, 4.50 m height) •
I: Cacti and Other Succulent Plants of the Americas (191 m2, 4.50 m height)
Connecting Greenhouses: •
D: Orchids and Pitcher Plants (231 m2, 3.30 m height) •
L: Carnivorous Plants and Plants of the Southern Hemisphere (231 m2, 3.30 m height
Highlighted greenhouses •
A: The Great Tropical Greenhouse (reopened in 2009 after extensive renovations) dominates the complex with its advanced design and environmental controls. •
O: The Victoria House and Marsh Plant House (restored and reopened later) features specialized aquatic and marsh plant collections. •
P: The Mediterranean and Canary Islands House is located separately, showcasing plants from those regions. A distinctive feature of these greenhouses is their innovative construction technique. Some, such as the subtropical greenhouse, have internal steel support frames, while others, like the Great Tropical Greenhouse, feature external steel frames. This design reduces heat loss, minimises condensation, and prevents dripping water on the steel beams, enhancing plant care and energy efficiency. The total floor area of the originally heated display greenhouses was 8,192m², supplemented by unheated "earth houses" for cold frames covered approximately 1,500m². This combination of functional design and technological advancements reflected the era's progress in greenhouse construction.
Redevelopment (1979–1987) Between 1979 and 1987, the greenhouses in the front row (
E to
K) were demolished and replaced with new structures designed by architect and artist Engelbert Kremser. This redevelopment was prompted by structural decay and the need for more space. Kremser utilised modern design principles, incorporating organic curves in the facades and roof transitions to evoke natural forms.
The Great Tropical Greenhouse The Great Tropical House, completed between 1905 and 1907, remains one of the largest steel and glass structures in the world. Designed by architect Alfred Koerner and structural engineer
Heinrich Müller-Breslau, it is considered Koerner's most significant work. Despite being over a century old, it continues to exemplify advanced architectural and engineering achievements of its time. The building measures 60.04 meters in length, 29.34 meters in width, and approximately 25 meters in height, covering a floor area of 1,728m² and enclosing a volume of 36,200m³. Its central planting bed alone spans 1,000m², with an earth depth of 3.50 meters. Beneath the central bed is a cellar room containing radiators for heating, supplemented by three rings of heating pipes integrated into the glass roof. These pipes, with a small diameter, are discreetly hidded from view. The structure features steel three-hinged arches on the exterior, while the glass façade is suspended on the interior. This design not only minimised heat loss but also optimised the building's aesthetic and structural integrity. For maintenance, three galleries encircle the interior and are accessible via the glass tower located at the rear of the building.
Impact of World War II The steel structures of the greenhouses survived the Second World War intact. However, in the autumn of 1943, the blast waves from nearby bomb explosions shattered most of the glass panes. This devastation left the tropical plants exposed to freezing temperatures, resulting in the loss of the majority of the collection. Despite this, some tropical plants reportedly survived, as dedicated employees safeguarded them in kitchens and living rooms until conditions allowed for their return. This resilience highlights the commitment of the staff to preserving the garden's unique botanical heritage during a period of immense hardship.
Post-war reconstruction and modernisation Reconstruction of the Botanical Garden's greenhouses began in 1949, with the Victoria House reopening in 1950. By 1958, nine greenhouses were once again accessible to the public. The reconstruction of the Great Tropical Greenhouse, a significant milestone, commenced in 1963 and was completed on 22 May 1968 at a cost of 3.45 million marks (equivalent to approximately 10 million euros today). The project included extensive modernization of the building's technical facilities.
Technical updates and innovations During reconstruction, the original silicate glass roof was replaced with acrylic glass, chosen for its advantageous properties, including reduced UV absorption, lower thermal conductivity, lighter weight, and improved malleability, allowing for larger panes (1 m × 2 m). However, a key disadvantage of acrylic glass became evident on 31 July 1969, when a fire in the upper dome caused significant damage to the plastic glazing resulting in over half of the plant life being killed. The affected area was repaired before the onset of winter, and the greenhouse reopened in June 1970. The heating system was also upgraded during the refurbishment. An air circulation system with 16 fans was installed in the vaulted cellar, distributing warm air via shafts at three different heights and cycling it six to eight times per hour. To maintain optimal humidity levels, a sprinkler system with 66 nozzles was added, capable of dispersing 130 liters of water per minute. Additionally, 96 high-pressure mercury vapor lamps of 400 watts each were installed to supplement lighting.
Upgrades in the 1960s During the 1960s renovation, the heating system of the Great Tropical House was thoroughly modernized. An air circulation system with 16 fans was installed in the vaulted cellar, distributing warm air through shafts at three different heights and cycling it six to eight times per hour. To maintain adequate humidity, a sprinkler system with 66 nozzles was added, spraying 130 liters of water per minute. Additionally, 96 high-pressure mercury vapor lamps, each with a power of 400 watts, were installed to enhance lighting conditions for the tropical plants.
Urgent repairs and renovations (2004–2009) By the early 2000s, the Great Tropical House required extensive refurbishment due to deteriorating conditions. In March 2004, the building was temporarily closed when rusted ceiling light suspensions posed a safety risk. In January 2006, heating damage in the neighboring Victoria House nearly caused a catastrophic loss of plants, highlighting the urgent need for repairs to the Great Tropical House. Many of its cracked glass panes had only been temporarily glued, and the heating system was at risk of failure. On 16 February 2006, the Berlin House of Representatives approved a comprehensive refurbishment project with a budget of 16 million euros. The funding was provided by Freie Universität, the Stiftung Deutsche Klassenlotterie, the Berlin Senate Department for Urban Development's environmental relief program, the BMBF's university construction program, and the European Union's European Regional Development Fund. To prepare for renovations, the plants were relocated to other greenhouses and a specially constructed temporary greenhouse. Renovation work began in August 2006, focusing on structural repairs and modernization. The Great Tropical House was ceremonially reopened on 16 September 2009 and opened to the public the following day.
Victoria House The Victoria House, designated for tropical aquatic plants, was situated along the central axis in front of the Great Tropical House. Measuring 10 meters in length and 8 meters in width, it originally showcased giant water lilies, which had been a major attraction in the old botanical garden. To maintain this tradition, the new botanical garden provided the Victoria House with a central position within the greenhouse complex. However, its current connection to the Great Tropical House was only established during renovations between 1966 and 1969.
Expansion and enhancements As part of these renovations, the Victoria House was expanded from 214 m2 to 254 m2, and a Swamp Plant House was added, providing an additional 170 m2 of floor space. The water basin in the Victoria House was enlarged from 70.3 m2 to 113 m2 to better accommodate the aquatic plant collections, including the iconic giant water lilies.
Redesign of the entrance and facilities During the same period, the entrance to the greenhouse complex was completely redesigned. A publicly accessible basement was added beneath the Victoria House, featuring two marsh plant basins and twelve aquariums displaying aquatic plants from around the world. This basement also included service rooms and, later, a shop and café (temporarily relocated to the museum during renovations). The basement provided direct access to the Great Tropical House and greenhouses G and H, serving as starting points for visitor tours. The newly redesigned greenhouse complex, including the expanded Victoria House and its improved facilities, was officially opened on 19 June 1969, marking a significant modernization of the botanical garden's infrastructure.
Renovation of Victoria House (2013–2018) While the Great Tropical House was completed in 2009, the Victoria House remained closed. Renovations for the Victoria House began in 2013, with an initial reopening planned for September 2015. However, construction defects caused delays, and the Victoria House ultimately reopened on 16 June 2018, marking the culmination of significant restoration efforts for both iconic greenhouses.
Mediterranean House A notable architectural highlight is the cold house for subtropical plants, also called the
Mediterranean House. Located a short distance from the main greenhouse complex to avoid shading, even during low winter sun, this greenhouse has a three-aisled structure and two portal towers, giving it a cathedral-like appearance. The house covers a floor area of 878 m2 and has a ridge height of 15.8 meters. It underwent a complete renovation between 1989 and 1992.
Colonial Garden Greenhouse The small greenhouse for colonial crops was situated in the colonial garden near the boiler house. Simple in design, it had a height of 3.70 meters and a floor area of 134 m2. This greenhouse no longer exists today. These structures reflect both historical functionality and modern adaptation, demonstrating the evolution of greenhouse design in response to scientific and environmental needs. == Other Structures ==