Greenhouses

Orchids (house 1)

Access to the orchid house is to the south of Hall A housing the Large Cacti. Orchids are prevalent here, as well as other plants thriving in warm and humid climates.

The many different flowering plants can only give a small glimpse of the abundance and diversity of tropical shrubs and herbs.

Soaring large tree trunks next to the central small water basin provide support for various air plants (epiphytes). Behind these, large Heliconias, which are related to the banana, flower almost all year long. Tropical plants from a variety of families thrive in the beds at the sides, coming into flower during different times of the season.

The jungle-like atmosphere is enhanced further by small tropical poison-dart frogs (Dendrobates auratus, Epipedobates tricolor) and their loud cricket-like chirping noise. However loud the noise, the frogs are very hard to detect.

Not all orchids need high temperatures to flourish. However, the most magnificent and precious among them come from such climates. Due to their exclusivity and great commercial value, many orchids have become almost extinct in their natural habitats. They have all been put on the endangered species list and their trade is regulated by law.

Orchids have a remarkable survival strategy. In most of the orchid families, the pollen is concentrated in a pollen packet (pollinium), whereas the pollen of other plants usually occurs as pollen dust. This is why the plant produces very large numbers of seeds after successful pollination. Over one million seeds per seed capsule have been recorded. The seeds are like dust particles and lack an endosperm, which makes them very light and able to float away like dust.
When the orchid seed encounters the appropriate fungus, it will enter into a symbiotic relationship. Having absorbed parts of the fungus hyphae, the seed begins to germinate. Usually, the orchid forms a lasting relationship with the fungus. While the fungus provides the orchid with various minerals, the orchid reciprocates with some surplus carbohydrates. In our greenhouses, the orchids thrive without their respective symbiotic fungi. Only a minute fraction of all the seeds released will germinate, as the chance for a seed to meet an appropriate fungus during its short lifespan is very small.

Audio points

• Introduction: The wide world of orchids
• What are Epiphytes?
• Orchids: Reproduction by seeds
• Perfume orchids: Scent as reward
• Orchids: Aerial roots with Velamen radicum
• Crescentia: Epiphyte host trees

Greenhouses

• Africa and Madagascar house (hall C)
• Aquatic plants (house 4 with aquariums)
• Bromeliads and aroids (house 8)
• Carnivorous plants (house 4a)
• Cycads (house 9)
• Desert plants (house 5)
• Grüner Saal (house 7 for exhibits)
• Large cactus house (hall A)
• Mexico house (house 6)
• Orchid house (house 1 with turtles)
• Palm house (hall B)
• Staghorn ferns (house 12)
• Temperate house (house 11)
• Tree ferns (house 10)
• Tropical economic plants (house 2)
• Victoria house (house 3)