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The Modern Art of Orchids Sign Panels

Throughout history, orchids have been seen as profoundly beautiful works of art-nature's masterpieces. In The Modern Art of Orchids, we present these alluring flowers in a contemporary setting that emphasizes the remarkable beauty that continues to capture our imaginations and passions today.

In addition to their legendary looks, orchids are spectacularly diverse. Orchids can be found growing naturally in every county in the world, on every continent but Antarctica. There are over 25,000 known species and more than 110,000 human-produced hybrids.

Varying wildy in size, shape and color, orchids account for 10% of all flowering plant species. Orchid species range from the size of a thumbtack to 40 feet tall. Some orchids, like the cymbidiums, have long, grass-like leaves, while others have thick, water-storing stems like cacti.

The flowers exhibit an almost endless diversity from spotted to striped to robust, rounded forms to sleek, starry shapes. The flowers can grow in massive clusters or as single, long-lived beauties.

You'll find orchids throughout the Conservatory, in addition to this exhibit. You can see them in the Potted Plants gallery, Aquatic Plants gallery and in our Highland Tropics gallery where we feature cool-growing orchids from the cloud forests of the tropical highlands.

Orchid Conservation
Throughout the world, orchid habitats are being destroyed as humans expand into the forests, jungles and other areas orchids call home. Because many orchid species are indigenous to a specific micro-climate. The destruction of that habitat leads to its extinction. And this isn't only in developing countries. San Francisco was once home to six orchid species, only two of which can still be found here today (Piperia elegans and Spiranthes romanzoffiana).

Another threat is the overcollection of orchids in the wild. There is a brisk trade in wild-collected orchids and they continue to be collected in large numbers from their native habitat often to the point of extinction.

Efforts are being made by governments, trade groups and orchid enthusiasts to stop the loss of orchids in situ (in place) by setting aside conservation parks and protected native habitats. Ex situ (out of the native place) cultivation consists of growing species away form their native place. Some species, like the Epidendrum ilense of Ecuador, are completely extinct in the wild and would be lost forever except that orchid breeders continue to propagate them.

What can you do to help? Don't contribute to the wild orchid trade, buy only nursery grown orchids. Consider donating to organizations that establish natural preserves. Take good care of the orchids you own.

What Makes an Orchid an Orchid?
It is the orchid's flower that distinguishes it from other plant families. Orchids tend to have fewer parts and many of those parts are often fused together. While there are enormous variations of these basic elements within the orchid family, they exist in almost every orchid.

• Each orchid flower has only three sepals and three petals. It is the backside of the sepals that we see when the flower is in bud form. The sepals open first and the petals then unfurl. One of the petals is usually modified into a pollinator-attracting landing structure called the lip.
• Orchids do not have separate stamens and pistils in their flowers. Instead, the stamens (male reproductive structure) and pistils (female) are united into a single central structure known as the "column." Rather than the dry, dusty pollen most plants produce, orchid pollen is held in waxy packets called "pollinia"
• One of the features that makes orchid flowers interesting is that the left and right sides of the flower are mirror images of each other, this is called bilateral symmetry. Many other flowers, like tulips and daises, can be divided into two equal halves on any plane through the center of the flower and will still mirror each other. This is radial symmetry.

Where Do Orchids Grow?
Orchids have adapted to almost every environment on earth. Orchids grow in swamps, sand dunes and grasslands. They grow in rain forests, coastal lowlands and semi-arid deserts. Orchids can be found in the dry scrub of Western Australia and the snow-covered Swiss Alps. They grow in Minnesota's peat bogs and throughout many of California's diverse environments. Many of these orchids are endemic, living only in a limited area such as a single canyon or hillside.

The richest diversity of orchids lies in the forests of tropical South America, Southeast Asia and New Guinea. Colombia is thought to be home to more than 3,000 orchid species, while New Guinea has over 3,200 native orchid species.

Many orchids grow in the hot, steamy jungles of these equatorial countries but the diversity and quantity of orchids increases in the higher altitudes of the tropics from approximately 3,000 to 10,000 feet.

The highland-dwelling orchids tend to be smaller and more delicately shaped than their lowland relatives. Accustomed to the cool temperatures of the tropical montane forest, these orchids are on display in our Highland Tropics gallery.

How Do Orchids Grow?
To survive in terrain as varied as the Arctic Circle and the tropical rainforest, orchids have developed a number of interesting growth habits. These include:

• Epiphytes growing upon other plants. ('Epi' is Greek for 'upon' and 'phyton' means 'plants.') Epiphytes are typically found on the branches of tall trees where sunlight is more available. These are not parasites and do not harm the host plant. 70% of all orchids are epiphytes including most of the popular orchids in cultivation.
• Terrestrial orchids growing in the soil. (This name comes from the Latin word for earth, terra.) Orchids like those found in the Arctic and the temperate climates of Europe, North America and Argentina are primarily terrestrial. They survive their harsh winters by going dormant.
• Lithophytes growing on rocks, in crevices and on cliff faces. ('Litho' means 'rock' in Greek.) These plants often have long roots that help secure the orchid to the face of the rock while seeking out nutrients from crevices along the rock's surface.
• Saprophytes grow from the humus layer on forest floors. They lack chlorophyll and the ability to photosynthesize (create their own carbohydrates). Saprophytic orchids depend upon fungus (mycorrhizae) in their roots to gain nourishment from decaying organic matter like fallen logs. The name comes from the Greek word, 'sapros,' meaning 'rotten.'

Living in Trees
Living in a tree canopy can lead to extreme climate conditions. Depending on how high in the tree the orchid grows, the sun can be scorching, the wind drying and water infrequent. Orchids have developed a number of adaptations to help them survive.

• Aerial roots not only anchor the orchid to the tree, they serve as water absorbing sponges. The roots are covered in a silver-colored layer of dead cells called, velamen, which absorbs water and nutrients for the plant.
• Pseudobulbs are a part of the leaf (petiole) that can swell to store water like the hump on a camel. Depending on the species, they come in a variety of shapes from squat globes to lean cylinders.
• Some orchids have thick, fleshy succulent leaves that store water, like a cactus. And, while most plants open the pores on their leaves during the day to draw in carbon dioxide for photosynthesis, the epiphytic orchid opens its pores at night avoiding evaporation of its precious water. The plant converts the carbon dioxide to an acid it stores and uses for photosynthesis during daylight.

As Small as Dust
When an orchid is successfully pollinated, a single orchid seedpod may contain as many as one million seeds, each as fine as dust. Orchid seeds may be the smallest seed of any flowering plant. One of the reasons for their microscopic size is the lack of endosperm--the starchy food supply that typically fuels the growth of a seed until it forms leaves and roots.

Instead of endosperm, orchid seeds develop a symbiotic relationship with a mycorrhizal fungus. The fungus acts as a conduit to provide nutrients to the developing seedling. In return, the orchid provides a home for the fungus.

In 1922, professor Lewis Knudson of Cornell University discovered that orchids seeds could be germinated without the fungal association by supplying nutrients like sugar and mineral salts to the seeds. Variations of Knudson's original formula are still used today.

Native Orchids
California is home to 32 species of orchids. Orchids are found in almost all of the state's 58 counties with the wet, northwest counties of Siskiyou, Del Norte, Trinity and Humboldt having the highest concentration with more than 20 species. Even Death Valley with two inches of annual rainfall is home to orchids.

San Francisco was thought to have had six native orchid species. Four of them, while not having gone extinct, have not been seen in San Francisco for decades. However, two species, ladies tresses (Spiranthes romanzoffiana) and coast piperia (Piperia elegans) can still be found.

The coast piperis is growing on several hilltops including Bernal Hill, Mt. Davidson and Twin Peaks. It typically blooms in summer and can be found throughout the Coast Range of California.

Ladies tresses can be seen in the Presidio. It also blooms in the summer months. These orchids are typically found in wet meadows and grow throughout California, the Southwest and throughout northeastern United States. These are both terrestrial orchids.

Wacky Pollination
Flowers exist in this world for primarily one reason; to attract pollinators. Rooted in place, plants must rely on outside sources to assist them in transferring pollen to produce seeds. Some plants rely on wind or rain to assist in spreading their pollen, but orchids rely almost exclusively on insects and other animals.

Over millions of years, orchids have developed some intriguing methods to ensure their pollination.

• Plants in the genus Ophrys fool male wasps and flies by mimicking the fragrance and appearance of a female insect. When the male attempts to mate with the flower, clumps of pollen stick to its body. The thwarted male moves on to deposit the pollen on the next 'potential mate' it finds.
• Some Oncidium species exploit the territorial nature of bees with flowers that look like the bee's antagonists. When a breeze kicks up and the flowers move, the bee attacks, butting the offending flower like a bull. With a forehead full of pollen, the bee flies off, only to get drawn into another floral battle.
• The Stanhopea flower's spicy scent is a promise of nectar to male euglossine bees. However, when they land on the flower, they slip on its slick surface and tumble into a bucket shaped structure. The only exit is through a series of internal paths, which allows the flower to deposit pollen on the bee's back as it exits.
• The Catasetum has a sensitive trigger which, when touched, causes the pollen to shoot out onto the bee's body where it sticks.
• After studying the long nectar reservoirs of the Madagascan night-blooming Christmas Star orchid (Angraecum sesquipedale), Darwin predicted that it would be pollinated by a moth with a tongue ten to eleven inches long. Darwin's fellow scientist dismissed the notion as laughable. Forty years later in 1903, a sphinx moth, with a twelve-inch proboscis, was discovered in Madagascar.

Art History
From the Greeks of antiquity to the Victorian British, just about every culture has fallen for the allure of orchids. But no group has cherished them as art pieces for as long as the ancient Chinese.

With more than 1,000 species native to China, orchids, called 'lan', have played a significant role in China for centuries. Over 2,000 years ago, Confucius wrote about the graceful leaves and delicate fragrance of orchids. He compared them to a true friend and equated the orchid's fragrance to the joys of friendship.

Shortly thereafter, in the sixth century B.C., the orchid became a common image in Chinese poetry symbolizing love and beauty. In the Northern Sung period (960-1279) the orchid, particularly the cymbidium, became a very popular subject for painters with its grassy, tapered leaves and the dynamic structure of the cymbidium flower.

In fact, when the Sung dynasty fell in 1279, one painter used his orchid paintings to represent his loyalty to the fallen emperor. He refused to add a background to his orchid paintings symbolizing the theft of his native land by the new Yuan dynasty.

The Samurai Orchid
In spring, don't put them outdoors.
In summer, don't expose to too much sun.
In autumn, don't keep too dry.
In winter, don't keep too wet.
-- Jo-an Matsuoka, 1728

The Japanese have a rich history of orchid appreciation. Orchids were long associated with particular social classes. Merchants cultivated cymbidiums, while the imperial class grew Dendrobium moniliforme, which were symbols of longevity.

However, no one but samurai were allowed to raise wind orchids (Neofinetia falcata). The Shogun of the late 1700s was passionate about these orchids and had a collection of more than 200 of them. Samurai would often travel accompanied by their orchids. The plant was an indication of the warrior's bravery as collecting this orchid in the wild would have meant facing many physical challenges.

The Tastiest Orchid
Vanilla comes from orchids. One of the few orchids with a commercial use other than flowers, vanilla is native to many areas of the tropics. But it is the vanilla from the Americas that is most prized for its flavor (Vanilla planifolia).

Vanilla's Aztec name was Tlixochitl and both the Aztecs and Mayans used it to flavor chocolate drinks. Prior to the Spanish conquest of Mexico, the Aztecs had developed botanical gardens and the vanilla orchid was a prized specimen.

The flavor comes from the seed pod, or the 'bean' of the vanilla plant. The slender, dark brown pod grows to about eight inches long and like all orchids, contain thousands of tiny seeds. The island of Madagascar off the east coast of Africa is now the world's largest producer of vanilla. Unfortunately, vanilla, like so many orchids, is pollinated by one specific insect-a bee found only in Mexico. In order to produce seed pods, all Madagascan vanilla must be hand pollinated.

In our Lowland Tropics gallery, you'll find a vanilla orchid vine climbing up the side of our giant philodendron.

Growing Orchids
It is interesting to note that one of the largest flowering plant families with members growing just about everywhere in the world has a reputation for being one of the most difficult plants to grow. With thousands to choose from, some orchids will of course be challenging and difficult to grow. But most of the orchids you'll find at your local nursery or florist will be no more demanding than most other houseplants.

The keys to growing orchids successfully?

• Find an orchid whose needs you can match with ease. Know what its temperature, light and water requirements are before you bring it home. Orchids come from steamy, humid jungles and cool, dry mountains. Find the orchid that suits you.
• Don't over water. This is one of the leading killers of orchids in the home. While some orchids like phalaenopsis and pahiopedilums like to be kept evenly moist, many of the orchids in cultivation, like cattleyas and dendrobiums, were originally epiphytes living high up in tree branches. They are accustomed to periods without water.
• Orchid light requirements can vary from low to high so discuss with your orchid seller the light quality of the place where you intend to grow your orchid. Too little light is as lethal to an orchid as too much light. Eastern and southern exposures are typically best for most orchids. Light from a western exposure can be too intense in the afternoon and northern exposures do not provide enough light for some species.

Keep an eye on your plant. Observation is probably your most useful tool. With regular observation you can detect a problem before it becomes a threat.

From One to Many
At one time, orchids were the exclusive domain of the wealthy. Orchids were difficult to cultivate and extremely hard to come by. Now, orchids are available at grocery stores. What happened to make them so widely available?

Commerical nurseries now mass produce orchids by tissue culture propagation. This is somewhat like growing a plant from a cutting, but on a larger scale. The process starts with a small piece (cell tissue) of a plant which is carefully cultivated in a sterile environment. At appropriate stages, the growing plants are divided and eventually transferred to pots. Growing laboratories can produce more than 250,000 identical new plants or "clones" in ten to twelve months. Tissue culture is also used in conservation and research. Since the plant is usually not harmed when the tissue is taken, endangered species that might be difficult to grow when removed from their native environment can be reproduced. Plants that may be difficult to grow from seed can also be readily reproduced with this process.