June 20, 2024

How to Grow and Care for Calanthe Orchids

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Beautiful Calanthe orchids are mostly terrestrial species that can be evergreen or deciduous. Learn about growing this unique group of plants at Gardener’s Path.

A vertical photo of a white clanthe orchid plant in full bloom. Green and white text span the center and bottom of the frame.

Calanthe spp.

Never was there such an aptly named plant. The genus name Calanthe combines “kalos,” which is Greek for beautiful, and “anthe,” which is Greek for flower.

Sometimes known as Christmas orchids, species in this genus are adaptable, elegant, and colorful, with some hardy enough to withstand temperatures at or even below freezing!

They make excellent houseplants, like many orchids, but they can also be used in landscaping in Zones 6 and up.

A horizontal photo of a dark pink calanthe orchid blooming in a tropical garden.A horizontal photo of a dark pink calanthe orchid blooming in a tropical garden.

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I understand why Phalaenopsis orchids are so popular as houseplants, but I’m baffled as to why more people aren’t enjoying Calanthe orchids in their homes and yards.

They’re long-blooming, and some are hardier than your more common species. But they’re every bit as beautiful as moth orchids.

Interested in these glorious plants? We’ll help you master the growing process. Here’s what we’ll go over to make that happen:

What You’ll Learn

  • What Are Calanthe Orchids?
  • Cultivation and History
  • Propagation
  • How to Grow
  • Growing Tips
  • Pruning and Maintenance
  • Species and Hybrids to Select
  • Managing Pests and Disease
  • Best Uses
  • Quick Reference Growing Guide

Because they generally grow in the earth rather than attached to trees and rocks, Calanthe species have some unique characteristics and growing requirements.

Before we talk about those, let’s understand a bit more about what sets these plants apart.

What Are Calanthe Orchids?

Calanthe orchids (ka-LAN-thee) are those in the Calanthe genus, which comprises about 200 species.

They are mostly terrestrial plants that come in two types, defined by the subgenera Eucalanthe and Preptanthe.

A horizontal close up photo of pale pink calanthe orchid blooms with dew on the leaves.A horizontal close up photo of pale pink calanthe orchid blooms with dew on the leaves.

Eucalanthe species are evergreen with a basal rosette of leaves and no pseudobulbs, with a flower stem that emerges from the center of the leaves. They grow in tropical to temperate areas.

Preptanthe plants are deciduous and lose their leaves in the cold winter of their preferred environments. The flower stalks form from pseudobulbs that are typically gray-green.

Evergreens include C. alismifolia, C. sylvatica, and C. triplicata, and deciduous species include C. hirsute, C. rosea, and C. vestita

You can’t breed the two different subgenera, which is one reason that botanists are considering separating the two into their own genera.

A horizontal shot of pink calanthe orchids growing in the forest under a shady tree.A horizontal shot of pink calanthe orchids growing in the forest under a shady tree.

The difference is important because it impacts how you’ll grow these plants.

Home gardeners tend to prefer the deciduous types because they have long-lasting inflorescences that can stick around for months.

Regardless of the type, they are all sympodial, which means they produce multiple flower stalks rather than a single stalk. All have pleated or corrugated leaves and many have clusters of oval-shaped pseudobulbs.

They can be found growing wild across the globe in tropical climates in Asia, Australia, Mexico and Central America, the West Indies, and the Pacific Islands. The vast majority of species are native to southeast Asia.

Heads up: lots of orchids are known commonly as “Christmas” because it’s the name given to those that flower in the winter. But not all calanthe orchids bloom in the winter, and not all Christmas orchids belong to the Calanthe genus.

C. discolor and C. triplicata are commonly called Christmas orchids and bloom in winter.

Cultivation and History

The Calanthe genus was first described and illustrated by Georg Rumph, a German botanist, in 1750 in his tome “Herbarium Amboinense.” He used a specimen from Indonesia. The genus was formally established in 1821 by Robert Brown, a Scottish botanist.

Back in the 19th century during the Victorian plant craze, Calanthe orchids were a floral status symbol. Over the years, they have taken a backseat to Phalaenopsis and Cattleya, which is a shame. They’re easy to grow, long flowering, and showy.

A horizontal close up photo shot from above of a pink calanthe orchid bloom.A horizontal close up photo shot from above of a pink calanthe orchid bloom.

One of the first orchid hybrids on record was a cross between C. furcata and C. masuca, bred by John Dominihy, a breeder who worked with James Veitch, who founded the famous Veitch Nurseries in England. It was called C. x dominii.

This was followed by a hybrid between C. rosea and C. vestita

These days, while they haven’t gained the same level of popularity as their cousins, they are popular in their own right, with lots of hybrids and cultivars on the market.

Calanthe Orchid Propagation

If you’re up for an adventure, it’s possible to propagate orchids from seed.

Note that I said it’s possible, but not easy. It takes some special equipment and a lot of time, but you might be able to breed something exciting and new.

A horizontal close up of a white blooming calanthe orchid with bright pink centered blooms.A horizontal close up of a white blooming calanthe orchid with bright pink centered blooms.

If you’re interested in the challenge, please visit our guide to propagating orchids from seed. Otherwise, let’s talk about division.

By Division

Both types can be divided, but Preptanthe plants actually grow better if you divide them regularly. That’s because two-year-old pseudobulbs die at the end of their second year. When you divide them regularly, you encourage new growth.

To divide, gently dig up a plant or pull it out of the container. Brush away the soil from the roots and locate a natural division in the plant that includes some roots and some pseudobulbs. Use a pair of clean scissors or pruners to sever the largest roots and then tease the plant apart.

If the plant has any back bulbs, which are the older bulbs that no longer have leaves, you can divide these and plant them individually.

Plant half back in the original pot or area of the garden and plant the remaining section in a new area or container.

Epiphytic orchids prefer that their roots be a bit crowded, but you can use larger containers with terrestrial species. Look for a container that’s about twice the size of the rootball.

Transplanting

Most of us purchase our first Calanthe orchids or receive them as a gift.

When you bring your first one home, you don’t need to repot it right away. But if you want to put it in the ground, it’s best to wait until mid-spring.

Prepare the ground by working in some well-rotted compost and making a hole twice as wide and the same depth as the growing container.

Gently remove the plant from its container and loosen up the roots. Lower it into the soil and firm the soil up around it.

The crown should be positioned at soil level or just below it. Don’t plant it more than just slightly below the soil surface or you run the risk of rot.

Gently water and add more soil if it settles too much.

How to Grow Calanthe Orchids

Generally speaking, evergreens should be kept moist to damp year-round, and deciduous types need to be allowed to dry out when the leaves have fallen. Let the medium completely dry out until new growth starts to form.

Both types prefer humidity between 40 and 80 percent.

While this varies by species, most prefer temperatures in the 70s or 80s during the day and around 50°F at night.

Sticking to the cooler end of the spectrum will result in longer-lasting flowers. Evergreens can tolerate cooler temperatures, with most being hardy down to around 5°F.

A horizontal photo of orange and yellow calanthe orchids in bloom with selective foreground focus.A horizontal photo of orange and yellow calanthe orchids in bloom with selective foreground focus.

Most need bright, indirect light indoors, and direct morning light is preferred. Outside, they do best in dappled shade or with an hour or so of direct morning light.

I will say that these plants can tolerate more light than most gardeners realize. Partial sun is perfectly fine for most species, so long as you expose them to the brighter light gradually over the course of a few weeks until they’re acclimated.

As with many houseplants that can tolerate bright light, growers cultivate these orchids in dimmer conditions than what’s ideal in order to acclimate them to the light available in most homes.

Without exception, mine have flowered better when I give them more light. Just avoid afternoon light, which is way too harsh.

Provide Preptanthe species grown indoors with a medium containing sphagnum moss, coconut coir chips, medium-size bark, and perlite. Don’t use a mix that is primarily orchid bark, which is marketed for epiphytes. You want some loam for the terrestrial orchids.

Outdoors, work a lot of well-rotted compost into the soil – the more the better.

The soil must be well-draining. If it isn’t, choose a container or a raised bed so you can control the medium and drainage. Or, if you have heavy clay, work in equal parts compost to the native soil at least two feet down and two feet out.

Either way, these plants prefer neutral soil, but they can tolerate a pH range between 6.0 and 8.0.

If you want to grow Eucalanthe species indoors, they must be exposed to temperatures just above 35°F for cool-growing species and 50°F for tropical species at night for two months to encourage new growth and blooming. That’s why most people grow them outdoors.

Keep in mind that while most Eucalanthe plants can grow as far north as Zone 6, some species are tropical and need warmer climates. Depending on the species, they need to be kept indoors during cold weather outside of Zone 9.

Outdoor plants don’t need a ton of fertilizer. Do a soil test and amend accordingly. Otherwise, you shouldn’t need to add fertilizer.

If you are growing yours in a container, change the soil every few years and fertilize once before flowering with a mild, balanced fertilizer.

Never fertilize a Preptanthe while it’s without leaves.

Growing Tips

  • There are two types of Calanthe orchids, so be certain you know which you have to provide the ideal environment.
  • Keep the soil moist but not wet, and allow deciduous types to dry out when they’re dormant.
  • Provide bright indirect light with direct morning light.

Maintenance

Resist the temptation to remove the leaves when they become crowded and untidy.

They are still providing vital nutrients to the plant, and removing them creates wounds that may expose the plant to viral pathogens. They shouldn’t be removed until they age to yellow and then brown and die off on their own.

Once the leaves turn yellow and collapse, you can remove them. They should just pull away, or you can use scissors to clip them off.

You can remove damaged or diseased leaves at any time.

A vertical shot of magenta colored calanthe orchids in pots.A vertical shot of magenta colored calanthe orchids in pots.

For tropical types, aim for 50°F at night and 60°F during the day for a month or so to encourage reblooming.

To protect outdoor plants that go dormant, place two inches of mulch over the soil in the fall after the leaves die back. Use an organic mulch like leaf litter, shredded bark, or compost. 

In USDA Hardiness Zones at the low end or even one below the recommended range of growing zones for a given species, it’s possible to keep plants alive with a thick layer of protective mulch. Make the mulch pile about a foot deep, covering the orchid and its root zone.

Remove the mulch in the spring when temperatures are regularly above freezing or if you see new growth emerging.

Container-grown outdoor orchids should be brought into an unheated garage or cold basement to overwinter.

Preptanthe orchids should be dug up and divided regularly. The pseudobulbs die after they’re two years old, so regular dividing will keep the plant going strong. Be extra careful when working with them because the pseudobulbs break easily.

Calanthe Orchid Species and Hybrids to Select

It seems like new cultivars are popping up all the time, but you can’t go wrong with any of the species or their hybrids.

Here are just a few of the prettiest and easiest to grow in home gardens or indoors:

Discolor

A popular evergreen or semi-evergreen in colder areas, the leaves of C. discolor can grow up to 18 inches long and form at the base of tall flower spikes dotted with up to 10 brown, white, green, and pale pink flowers.

A horizontal closeup of a blooming Calanthe discolor orchid with white blooms and dark red leaves.A horizontal closeup of a blooming Calanthe discolor orchid with white blooms and dark red leaves.

This species grows indigenously in Japan, Korea, and China. It has become wildly popular as a house or garden plant and is often used as a parent for hybrids.

Kozu

Kozu hybrids are absolutely well worth seeking out.

These hybrids are a cross of C. discolor and C. izu-insularis, and produce flowers in pink, purple, red, white, and yellow, depending on the cultivar.

A vertical profile of a pale yellow calanthe orchid bloom.A vertical profile of a pale yellow calanthe orchid bloom.

‘Kozu Spice,’ for example, is an evergreen indoors or in Zones 7 to 9 or semi-evergreen in Zone 6.

It was bred in 1996 in Japan by K. Karasawa, and has large white and purple blossoms.

Nipponica

Native to Japan and Tibet, this species grows in mountainous regions. It has bright green and light yellow flowers on tall stalks.

Each 15-inch stalk can produce up to 10 flowers. A member of the Preptanthe subgenus, C. nipponica can be grown outdoors as far north as Zone 6.

This species was first described by Japanese botanist Tomitarô Makino in 1898, and it has become a popular option for breeding hybrids.

Reflexa

This Japanese evergreen has underground pseudobulbs bearing two or three leaves up to nine inches long and three inches wide at their largest.

Each plant will only develop four or five flowering spikes at a time. These can reach up to 13 inches in height and initially feature nodding buds that eventually open and face upward.

Plants can exhibit up to 25 white and purple, pure purple, or pure white flowers at a time and they may bloom all together or open sequentially, starting in July and lasting through September.

C. reflexa grows in warm areas in wet woodlands or along stream banks, which tells you that this is a plant that needs lots of moisture.

Sieboldii

Hailing from Japan, this hardy evergreen has 18-inch tall inflorescences with bright yellow blossoms.

C. sieboldii is one of the largest plants in the genus and will survive temperatures down to 10°F.

A vertical close up of the dew on the yellow blooms of a calanthe orchid plant.A vertical close up of the dew on the yellow blooms of a calanthe orchid plant.

While the flowers aren’t the showiest, they’re eye-catching in their own right.

Combined with the large, pleated leaves that resemble hostas, C. sieboldii is a beautiful garden option.

Striata

With large, heavily flowered spikes of golden yellow blossoms, this hardy type drops its leaves in late summer and perks back up in early spring.

A horizontal photo of many yellow calanthe orchids blooming in a forest.A horizontal photo of many yellow calanthe orchids blooming in a forest.

C. striata is a good option for beginner growers because it’s adaptable and tolerant of a wide range of conditions. Those masses of pretty blossoms don’t hurt, either.

Takane

A hybrid cross of C. striata and C. discolor, C. takane is one tough orchid.

It can tolerate cold conditions and will still produce abundant cream, yellow, apricot, and pink blossoms on 18-inch spikes. It’s hardy to Zone 7, with pleated leaves similar to a broadleaf plantain.

This hybrid is a good option if you want something that will gently spread around the garden without becoming invasive.

Tricarinata

This popular, semi-evergreen species has lime-green and brown flowers on upright inflorescences that grow up to 12 inches tall.

A horizontal close up photo of a wild yellow calanthe orchid .A horizontal close up photo of a wild yellow calanthe orchid .

Provide C. tricarinata with loamy, rich, loose soil and keep it consistently damp. It should be placed in shade, but a little morning or dappled light is fine.

Vestita

This beautiful species hails from the Philippines, Thailand, Vietnam, Java, and Malaysia, where it is a deciduous epiphyte.

C. vestita requires dappled shade or morning sunlight and a humus-rich, loose, moist growing medium.

Each pseudobulb produces three or four oval-shaped leaves that drop from the plant each fall and regrow in the spring.

One inflorescence with up to 20 three-inch-wide white and yellow or red – depending on the climate and light – flowers emerge in July from each pseudobulb.

Managing Pests and Disease

Christmas orchids are surprisingly tough for such delicate-looking plants. The main problems to watch for are spider mites and root rot.

Pests

There’s one type of pest that plagues these orchids, whether indoors or out, and that’s the spider mite.

Spider mites are itty-bitty tick relatives that use their sucking mouthparts to draw out the sap of plants.

They can cause serious damage to the leaves of these plants, and can eventually kill them, especially young specimens.

Spider mites are so small that you might not notice them at first. You’ll probably see the fine webbing they create, often filled with small black flecks, or the splotchy, yellow leaves they cause.

The first step with eradicating spider mites is to isolate the plant if you can. Then, spray down the plant once a week with a gentle stream of water to knock the pests loose.

If that’s not working, read our guide for more tips on how to control spider mites.

Disease

Spots on the leaves are one of the most common signs of disease.

The Erwinia and Acidovorax species of bacteria cause leaf spots, as do species of fungi in the Cercospora genus.

Anthracnose, caused by fungi in the Colletotrichum genus, can also cause spots with tan centers and a black margin to form.

These pathogens spread by hitching a ride in splashing water, or in crowded conditions and high humidity. That’s why it’s important to water the soil rather than sprinkling the leaves, and keep plants well-spaced.

The moment you notice spotting, trim off any symptomatic leaves. Then, grab a biofungicide and bactericide combo, such as Monterey’s Complete Disease Control.

This product contains Bacillus amyloliquefaciens strain D747, which kills many pathogens.

A square product photo of the Monterey Disease Control product line.A square product photo of the Monterey Disease Control product line.

Monterey Complete Disease Control

Pick some up from Arbico Organics in 32-ounce ready-to-use or eight-ounce, pint, or gallon-size concentrate containers.

Root rot can be caused by water molds in the Pythium and Phytophthora genera.

When these pathogens are present, it can cause black, soft spots on the leaves or roots. Root rot can also be caused by overwatering, which drowns the roots.

A horizontal shot of a white calanthe orchid blooming in a garden.A horizontal shot of a white calanthe orchid blooming in a garden.

If you see unusual patterns and colors on leaves, it’s usually a sign that viruses like Odontoglossum ringspot virus (ORSV) and Cymbidium mosaic virus (CyMV) have made their way into your plants.

There’s no known cure, so you must either dispose of the plant or accept the unusual appearance. If you decide to live with it, know that the virus might spread to other orchids.

Learn more about these and other diseases in our guide to orchid problems.

Best Uses for Calanthe Orchids

Indoors, plants of either subgenus can be potted up and enjoyed. Some gardeners grow Preptanthe species in shallow trays or bonsai pots to highlight the unusual pseudobulbs.

A close up horizontal shot of a white calanthe orchid blooms with bright pink edged petals.A close up horizontal shot of a white calanthe orchid blooms with bright pink edged petals.

In the winter, when the leaves are gone and just the long pseudobulbs and tall flower stalks remain, species like C. vestita will make a centerpiece that draws comments.

Outdoors, they work well in groups, borders, specimens, or rock gardens, depending on the species.

Combine them with partial shade lovers like aralias, astilbe, bleeding hearts, ferns, hellebores, hostas, and trilliums.

Because these species are mostly terrestrial, you can’t mount them unless you’re growing one of the few epiphytic types.

Quick Reference Growing Guide

Plant Type: Sympodial evergreen or deciduous herbaceous flowers Flower/Foliage Color: Pink, purple, red, white, yellow/green
Native to: Asia, Australia, Central America, South Africa, South America Maintenance: Moderate
Hardiness (USDA Zones): 6b-9b Water Needs: Moderate to high
Bloom Time: Spring, summer, fall, winter, depending on species Soil Type: Loamy, rich
Exposure: Partial shade or bright, indirect light with morning sun Soil pH: 6.0-8.0
Time to Maturity: Up to 3 years from seed Soil Drainage: Well-draining
Planting Depth: Same depth as growing container (transplants) Companion Planting: Aralia, astilbe, bleeding heart, fern, hellebore, hosta, trillium
Spacing: 1 foot Uses: Borders, mass planting, potted (indoors and out), specimen
Height: Up to 3 feet Family: Orchidaceae
Spread: Up to 2 feet Subfamily: Epidendroideae
Growth Rate: Moderate Genus: Calanthe
Tolerance: Frost (some species) Subgenera: Eucalanthe, Preptanthe
Common Pests and Diseases: Spider mites; leaf spots, root rot, viruses Species: Alismaefolia, callosa, hirsute, lutea, odora, rosea, rubens, striata, styloglossum, sylvatica, tricarinata, triplicata, vestita, yueana

Celebrate Christmas All Year Round

Calanthe orchids are special. They grow in the ground, and many can tolerate much colder temperatures than many of us associate with orchids.

The appearance of the foliage and the flowers can be truly remarkable, as can the pseudobulbs when highlighted in a shallow tray.

A horizontal close up photo of a single white calanthe bloom with a blurred background.A horizontal close up photo of a single white calanthe bloom with a blurred background.

Which species do you find most appealing? How will you grow it? Let us know in the comments section below and feel free to share a picture!

And for more information about growing orchids, have a read of these guides next:

  • Orchids 101: How to Grow and Care for Orchids
  • 23 Types of Orchids to Grow as Houseplants
  • How to Encourage Orchids to Rebloom

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