AboutOrchids

Considering its tiny flowers, this unusual Domingoa can really put on a show. Its thick, speckled leaves produce long stems with tiny purple blossoms. This plant can stay in bloom for more than two months, putting out successive flowers over late summer and early autumn.

I’ve had this Domingoa growing outdoors and blooming well for three years, but the flowers are so small that it’s been tough to take nice photos. Dave took some great shots recently, so I can finally share this little gem. Each flower is about 1/4 inch (6 mm) wide. Small bunches swing at the ends of spikes, or flower stems, which can grow over 1 foot (30 cm) long. The wiry spikes may look dead after blooms finish, but they can rebloom for years.

White and red speckles on the thick leaves keep this orchid interesting, even when it’s not flowering. Here on the California coast, it grows outdoors on a mount in partial sun. I keep it well-watered until winter dormancy, when I bring it indoors and cut back watering. It stays in our back room, where winter nighttime temps go down to 50°F (10°C,) until spring.

Native to parts of Mexico and Central America, this species recently underwent a name change from Nageliella to Domingoa. It’s an uncommon orchid to find, and it’s often listed under its old name. No matter what it’s called, it’s easy to find space for this charming mini in any collection.

In the Richmond Times-Dispatch, orchid expert Arthur Chadwick explains how to make orchids look their best. Whether you want your blooms to win a ribbon or to dazzle in a photo, it helps to know orchid grooming basics. Good presentation enhances orchid beauty. Some of the tips include:

• Stake flower spikes upright. Add stakes to Phals, Paphs, and Oncidiums while their spikes are still small. Wait to stake Cattleyas until buds are mature. Dendrobium spikes are strong enough that they don’t need staking.
• Flowers should all face the same direction. Do not turn plants while buds are developing, or they will reorient to the light and be askew. You can turn plants after all flowers are fully open.
• Plants should look happy and healthy. Remove dead or damaged leaves with sterile blades. Clean any dust or debris from the leaves.

Orchids can grow just about anywhere, but growers need to consider their latitude. Degrees of latitude show distance north or south from the equator. Sunlight levels and day length vary greatly at different locations, and knowing your latitude helps you understand how much or how little sunlight is available over the seasons.

• Find your latitude online
• Find the latitude of a city near you
• See how latitude affects hours of daylight

Horizontal lines, or parallels, represent latitude on the globe. Starting from 0° at the equator, latitude lines run up to 90° north at the North Pole, and down to 90° south at the South Pole. (On the other hand, longitude lines show distance from the Prime Meridian in the UK, and aren’t related to sunlight levels.)

Here in San Francisco, at approximately 38° north of the equator, we share a parallel with St. Louis, Missouri, Washington DC, Athens, Greece, and Seoul, South Korea. That doesn’t mean that we have the same climates, but we do share sunlight levels and day length. South of the equator, approximately 38° south, Melbourne, Australia and Auckland, New Zealand share similar sunlight levels and day length, but six months apart from their northern counterparts.

Commonly grown orchids come from the tropics, a region centered around the equator. Here, the sun’s strength and daylight hours vary little with the seasons. That’s why orchids prefer consistent light levels all year. Orchid growers in the tropics don’t need to worry about latitude’s effects on their light levels.

Orchid growers in temperate zones of the world experience big variations with the seasons. Just as the tilt of the earth creates the seasons, it also causes big swings in sunlight levels. Summer brings the sun high in the sky, and longer hours of light. In the winter, the sun is lower in the sky, with less hours of light. Orchid growers in temperate areas should supplement sunlight over winter. This simulates the high sunlight levels of the tropics. Temperate regions include most of the USA, Canada, Europe, Australia, and Asia. In these regions, adjusting for your latitude will help keep your orchids happy.

From Alabama to Zululand, September is a busy month for orchid shows. Australia, New Zealand, and South Africa have packed schedules. There’s plenty in the Northern Hemisphere, too. Here in San Francisco on September 28-29, Orchids in the Park combines a show and sale with seminars and demos.

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We’re celebrating a milestone in our garden: orchids which have been in continuous bloom for over a decade! These brilliant red Epidendrums have thrived outdoors here in San Francisco, surviving 10 years of strong winds, heat waves, grey winters, heavy rains, close to freezing temps, occasional hailstorms, and battles with raccoons. Through it all, they’ve kept their blooms. Typically, each plant boasts more than a dozen flower clusters rising above it.

Reed-stem Epidendrums come in a wide palette of brilliant colors, and are well suited for outdoors in tropical and sub-tropical areas. Individual flowers can last for many weeks, and new ones are constantly opening. And I must admit that they’ve bloomed for so long that I take them for granted in the garden scenery. They were originally a gift from an acquaintance living in San Francisco’s Forest Hill neighborhood. She had found them growing wild in her garden many years earlier, when she first moved into her home.

These vigorous plants frequently form seed capsules after pollination by Anna’s Hummingbirds. The capsules take several months to swell up, and then burst open, releasing clouds of minuscule seeds to float in the wind. Seedlings can grow to flower in three years. The mature plants also continually make keikis, so they’re easy to share, and I’ve given many to friends and neighbors over the years. It’s a guarantee that these tough orchids will be around for decades to come.

What do Brazil nuts have to do with orchids? Their relationship illustrates the complex links between rainforest residents. The nuts grow on massive trees in the Amazon, and rely on bees to pollinate their flowers. The bees, in turn, rely on orchids. Male bees collect orchid fragrances to lure females. They prefer the sweet scents of the unusual Bucket Orchid, Coryanthes vasquezii, a Stanhopea relative. “The more orchids, the more bees; the more bees, the more Brazil nuts.” This interdependence is one of the reasons why these trees are extremely difficult for farmers to cultivate, and the crop is collected from the wild. Brazil nuts, orchids, and bees link together in the intricate fabric of Amazon life.

From forests in the mountains of Japan and Taiwan, the Yellow Pine Orchid boasts clusters of colorful flowers. This cute mini orchid is Gastrochilus japonicus, a Vanda relative.

This species blooms with tiny flowers dangling beneath its leaves. The entire flower cluster is only 1.5 inches (3.8 cm) wide. Since the blossoms hang below the plant, it’s best to grow this variety on a mount. The Yellow Pine Orchid needs regular water and high humidity.

During winter dormancy, water the plant a little less, but don’t let it dry out. I move this specimen to a winter home in the back of our apartment, where it goes down to 50°F (10°C) at night, and receives slightly brighter light. I’ve found that if it doesn’t have a cooler winter, the leaves become covered with pests such as scale.

The next photos show the flowers opening with some buds still developing, and also the open flowers positioned underneath the leaves. They show what makes the Yellow Pine Orchid an unusual and adorable gem.

Two recent news stories highlight fascinating discoveries about orchids. First, from the Imperial College of London, there’s news about orchid trickery. Scientists studied Trichocentrum ascendens, a member of the Oncidium family. Its cheery yellow blooms don’t have any reward for its pollinators. Instead, it mimics flowers of neighboring plants which are full of oil. The orchid tricks bees into visiting, and they pollinate the plants. The flowers may look distinct to human eyes, but the ruse is meant for bees. Biology professor Vincent Savolainen explains:

“These reward-giving flowers have evolved a very special colour called bee-UV-green, that is highly distinguishable to bees’ sensitive eyes. The Trichocentrum ascendens and other Oncidiinae orchids copy the special colour so precisely that bees are unable to distinguish between the flowers, visiting an orchid and pollinating them without the reward they may expect.”

Next, AoB Blog reports on an orchid pollinated by raindrops. Acampe rigida is a pretty Vanda relative which lives in Southeast Asian jungles. It flowers during rainstorms. This is unusual, since most orchids bloom during dry weather. Scientists observed raindrops knocking around the Acampe pollen, causing the flowers to pollinate themselves. This is the first time this strange reproduction method has been proven for any plant. It’s an innovative strategy, allowing this species to take advantage of a pollinator which is as reliable as rain.

Are your orchids shrinking instead of growing? Changing your orchid care can help your plants grow larger. Healthy plants expand over the years. Added leaves can translate into added flowers. While bigger isn’t always better, it’s often an indication of vigorous plants.

Address any of these potential problems which can cause orchids to shrink:

• Low light – Many varieties can survive for a long time in low light without blooms or new growth. They may shrink slowly enough to avoid notice, but eventually they die back. Healthy orchid leaves should be a light or medium green color; dark green leaves can mean inadequate light levels.
• Low light in winter – If your plant grows during spring and summer, but shrinks during winter, add supplemental light. In autumn, move plants gradually into brighter positions, or add fluorescent lights. In spring, move plants back into normal light.
• Watering problems – The wrong amount of water can cause orchids to shrink. Whether it’s too little or too much water, roots become damaged, inhibiting growth. Never let orchid roots sit in water or stay saturated, or they may rot.
• Low humidity – Orchids don’t like dry air. Raise humidity levels by grouping plants together, using a spray mister, or keeping pots on trays of pebbles and water, with the pots always kept above the water level.
• Old potting material – Decomposing, stale potting material damages new roots, and stunts plant growth. Check these tips to see if your orchid needs repotting.
• Pests or disease – Insects and infections can kill all or part of a plant. Try beneficial insects and carnivorous plants. Use non-toxic pesticides when necessary, like Neem Oil, BT, pyrethrins, or rubbing alcohol/surgical spirits. Address underlying concerns which encourage pests and disease, like low humidity or poor air movement.
• Not enough fertilizer – Orchids don’t need much fertilizer, but nutrient deficiencies will inhibit growth. Fertilizing orchids weakly, weekly works best.

Are these orchids really black? Though common in fantasy novels and perfume names, black orchids exist only in legend. Even varieties which appear black are actually dark purple or dark brown. The fact that they don’t exist in nature doesn’t stop the orchid world from trying. Many orchid breeders labor to turn myth into fact by raising ever darker hybrids.

These almost-black orchids exude exotic beauty, intrigue, and mystery. Many have “black” or “midnight” in their names, like the Black Orchid which is the national flower of Belize. Members of the Dracula and Paph families above, and the Catasetum and Oncidium families below, show how closely these flowers approach an ebony color.

Some of these orchids are dark enough to inspire the claim to being black, but some just seem to be wishful thinking, or an attempt to boost flower sales. The Coelogyne and Cymbidiums below don’t need to claim an obsidian pedigree to look classy and luxurious. Maybe orchid hybridizers or scientists will someday create the elusive color, and finally claim the title of a truly black orchid. Until then, the black orchid legend lives on.