Often referred to as ‘Christmas Orchids’ because of their winter bloom time in tropical regions, species in the Calanthe genus got their botanical name from the Greek words for beautiful (kalos) and flower (anthe). Hardy in zones 7 through 11, Calanthe orchids are terrestrial, which means they are grown in soil rather than air. That sets them apart from other more demanding orchid species and makes them much easier to care for.
Calanthes are a popular houseplant and make a wonderful holiday gift. Flower colors include pink, red, purple, white, and yellow. When grown outside, they tolerate more shade than most orchid genera and multiply rapidly.
Let’s look a little closer at these unique members of the orchid clan and learn a little about their history, growing preferences, maintenance needs, and problem areas.
Calanthe Orchid Overview
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About Calanthe Orchids
Calanthe orchids, native to South Africa and Asia, include 200 varied species.
Native to the tropical and subtropical regions of South Africa and Asia, Calanthe orchids are perennial plants from the Orchidaceae family, which houses 880 genera, 28,000 species, and nearly 300,000 varieties of orchid. There are 200 species within the Calanthe genus and two sub-genera: Eucalanthe, which includes the evergreen species, and Preptanthe, which includes the deciduous species.
Classified as sympodial orchids, which means they have multiple stems rather than one singular stem (monopodial), Calanthe orchids feature several upright to slightly arching stalks with numerous blooms. Most species have a clove-like scent and relatively small flower sizes. Leaves are typically elliptical and spirally arranged. Their roots are thick, and pseudobulbs (an above-ground water storage node) are small when present. Evergreen species do not have any pseudobulbs at all.
Growing Calanthe Orchids
Considered one of the friendliest orchids for novice gardeners, Calanthes can be grown inside as a houseplant or outside in the ground or a container. In zones 7 through 11, they can be left outside year-round and will return perennially. In cooler zones, they’ll need to be brought in for winter. Here’s a look at the Calanthe orchid’s basic growing preferences.
Soil
Plant calanthes in well-draining soil, using specific mixes or amending ground soil for optimal growth.
Unlike many of their orchid relatives, Calanthes grow in soil. Proper drainage is a primary planting objective because they are highly susceptible to root rot. For houseplants or container gardens, use a potting mix designed for hardy (terrestrial) orchids or one featuring organic additives like hummus and pine bark. You might also add a substrate layer of gravel to the pot’s lower quarter to encourage thorough drainage.
For ground installation, amend soil (ideally in the previous season) with compost, peat moss, or another organic material to achieve a rich, loamy, well-aerated soil content with a neutral pH level. Mound soil up before planting to achieve some elevation and prevent puddling.
Depth & Space
Plant calanthe orchids with crowns slightly elevated, ensuring proper spacing and suitable containers.
Calanthe orchids should be planted at a depth that keeps their crowns slightly elevated (about two inches above the soil surface). Dig a hole wide enough for roots to radiate outward without overlapping or butting up against the hole’s perimeter. This rule applies to both container and ground plantings.
If planting more than one Calanthe orchid, space them between 18 inches and two feet apart to allow for expansion and proper airflow. If planting in a container, choose one taller than it is wide, and opt for terra cotta or something porous that will wick moisture away from roots.
Light
Plant Calanthe orchids in partial shade, favoring east-facing windows indoors or shaded areas outside.
Calanthe orchids thrive in partial shade and prefer dappled or filtered light to direct light. Houseplants should be located in a north or east-facing window where they will not be blasted with harsh rays. They can also be placed under soft fluorescent grow lights to mimic natural part-shade conditions.
Outside, a location under a tree or on the east side of a structure or shrub is ideal. If you must choose between morning or afternoon sun, always choose the former, and err on the side of more shade rather than more sunlight. Calanthe orchids are one of the few orchid groups that can perform well in very low light.
Water
Keep Calanthe orchids moderately watered, adjusting watering frequency based on species and local conditions.
Moderation is the key to keeping your orchids well-watered. Deciduous species will tolerate a small amount of drought but will perform better in soil that is kept evenly moist. Use a soaker hose once or twice a week, depending on climate and precipitation levels, to ensure they receive about one inch of water per week. As soon as leaves drop and plants have entered dormancy, discontinue supplemental irrigation until new growth appears in the next cycle.
Evergreen Calanthes demand the same, even watering practices but a higher humidity level than their deciduous cousins. They also require year-round irrigation, even during slow growth periods.
Monitor your local precipitation and humidity levels (they should be somewhere between 40 and 80 percent, ideally). If your local weather patterns do not meet these saturation points naturally, supplement them with a misting wand or spray bottle and a soaker hose.
Temperature
In zones 7 to 11, most Calanthe orchids withstand winter, with mulch adding extra protection.
Calanthe orchids can be safely left outside during winter in zones 7 through 11. There is some wiggle room in zone 6 if winter is mild and mulch is used to insulate the ground during dormancy.
Deciduous species can live and flower normally in temperatures between 50 and 85 degrees Fahrenheit. Evergreen species vary in their tolerance for cold, but some can endure temps as low as five degrees.
Fertilizer
Monthly or bi-weekly, provide a diluted, balanced liquid fertilizer to Calanthe orchids in an active growth phase.
Feed your Calanthe orchids monthly or bi-weekly while actively growing with a balanced liquid fertilizer (equal parts nitrogen, phosphorous, and potassium) that’s been diluted slightly.
This will keep sensitive leaves and blooms from being burned by an overzealous application. Water generously before and after feeding them and discontinue when leaves have dropped, or plants have entered dormancy.
Maintenance
Though Calanthe orchids are considered easy to care for, there are a few maintenance tasks you should perform to keep them moist, tidy, insulated, energized, and disease-resistant.
Mulch
Mulch Calanthe orchids with a moisture-retaining material.
Calanthe orchids should be mulched with a material that will retain moisture without compacting or overly saturating the soil. The medium should also decompose slowly and not consume excessive nitrogen.
For houseplants and container-grown Calanthes, use a thin layer of lightweight bark mix specifically designed for orchids. In the yard, apply a two-inch layer of cypress, fir, or pine chips around your Calanthes, pulling the medium slightly away from their crowns. After winter cutbacks are made, especially in cold zones, pile mulch up to a depth of three inches for a little extra protection.
Deadhead
Deadhead your Calanthe after flowering to encourage new blooms by snipping stalks near the base.
Your Calanthe should be deadheaded after flowering is complete and most of its petals have dropped. This will tell the plant’s roots to nourish new blooms.
To perform this task, use a clean, sharp pruning tool to snip flower stalks off near the base. Direct your cut to a location just above the second or third node from the crown; some varieties will give you another flush of blooms.
Prune & Cutback
Prune dead leaves and pseudobulbs for disease prevention and healthy Calanthe growth.
To prevent disease and encourage healthy new growth, prune off dead leaves and pseudobulbs when you notice them. This is the only regular pruning task you should have to perform on Calanthe orchids.
Houseplants do not need fall cutbacks and will retain leaves year-round, but outside orchids should be cut back to about two inches above ground level after the foliage has withered from the first frost.
Repot
Repot container-grown Calanthe every 2-3 years, trimming roots and dividing if necessary.
Container-grown Calanthe orchids have root systems that expand horizontally at a rapid pace. They should be repotted (and possibly divided) every two to three years to prevent crowding. Here’s how it’s done:
- Carefully remove your orchid from its current container.
- Trim away any decaying roots.
- Divide your orchid if rhizomes have more than two or three upshoots and pseudobulbs (see Division above).
- Select a well-draining container that’s porous and large enough to accommodate your Calanthe’s lateral root system.
- Fill halfway with a fine-grade potting mix designed for terrestrial orchids, or work some perlite, sphagnum peat moss, or orchid pine bark into the mix.
- Adjust the soil level so the plant’s crown will sit 1-2 inches above grade and fan the roots out in a circle.
- Cover loosely with the remaining potting mix, place in bright indirect light, and water evenly until established.
Overwintering
Container plants need winter shelter in cooler zones.
In zones 7 to 11, Calanthe orchids that have entered dormancy can be left in the ground and covered with a thick layer of mulch. In cooler zones, where temps typically dip below 14 degrees in winter, containers should be sheltered in a cool, dark location where temperatures hover around 50 degrees Fahrenheit and humidity levels are around 50 percent. Houseplants need no special winter care but require less frequent watering.
Propagation
Because they are expensive and much sought-after plants, orchids are often harvested illegally from natural settings, which has led to many species being labeled endangered. Calanthe orchids do not spread naturally by seed or germinate without considerable intervention, but there are two primary ways to propagate an established plant with relative ease: by division and by keiki.
Division
Divide and replant Calanthe orchids by separating rhizomatous roots and pseudobulbs every few years.
As sympodial orchids, members of the Calanthe genus have rhizomatous roots that extend laterally beneath the soil’s surface and offer multiple points of new growth. From these roots, which are narrow and long like a skinny sweet potato, green shoots emerge upward and break through the ground. These shoots can be separated and replanted every few years. Here’s how it’s done:
- Dig up your orchid and lay it flat on a hard surface.
- Dust off as much dirt as possible.
- Identify the rhizome, the roots, and the pseudobulbs (when applicable).
- Use a clean, sharp knife or pruning tool to divide roots into multiple sections.
- Include a chunk of rhizome, some roots, and two to three pseudobulbs (if working with a deciduous Calanthe species) in each new section.
- Replant as you would a new Calanthe orchid (see Planting below).
Keikis
Calanthe orchids produce keikis, or baby plants, which can be separated and planted independently.
A Hawaiian word that translates to ‘little ones,’ a keiki is essentially a baby orchid that grows from plant tissue above ground. Calanthe orchids grow keikis to varying extents and for diverse reasons ranging from reproductive security to stress and poor health. You may find that your Calanthe produces many keikis, an occasional keiki, or none at all.
Because they are reproduced asexually, keikis are true to the mother orchid. Look for them on spikes along your Calanthe’s stems at points near a growth node. They will be miniature versions of the mother plant, with small leaves, flowers (sometimes), and roots that dangle downward. These plants can be separated and planted independently. Here are the steps:
- Leave the keiki in place until its roots are between one and three inches long and it has a small upward shoot.
- Separate the spikes from the main stem with a sharp, clean knife or pruning tool.
- Apply cinnamon or an organic fungicide to the wounds on both the mother orchid and the keiki.
- Plant the baby Calanthe in a well-drained container with potting mix and keep it moist.
Popular Varieties
With roughly 200 species in the Calanthe genus, there are diverse options to select from. Here’s a quick look at the most prominent species and a summary of their characteristics and growing preferences.
Common Christmas Orchid
Cultivated for their classic white flowers, Christmas orchids thrive indoors, blooming from October to February.
Cultivars from this species are perhaps the most well-known Calanthe orchids. Snow-white petals and sepals are egg-shaped with a prominent lower lip in classic orchid form. Inflorescences are long and arching, producing anywhere from 10 to 40 flowers and reaching heights of up to 40 inches.
Leaves are evergreen and strongly ribbed, growing as long as 20 inches. In tropical regions (and inside warm homes), C. triplicata blooms from October to February, which is how this species earned its holiday name.
Bloom periods are particularly long, averaging somewhere between three and four weeks. Common Christmas orchids will behave perennially in the ground in zones 9 and 10 but are most often kept as houseplants.
Japanese Hardy Orchid
Durable in zones 7-9, this Eucalanthe orchid has evergreen foliage and yellow flowers in spring.
Hardy in zones 7 to 9, this Eucalanthe orchid features a pleated, basal leaf base that averages six inches tall and 15 inches wide. Its foliage remains evergreen year-round unless temperatures dip below 14 degrees Fahrenheit.
Flower stalks are thick and strong, reaching heights of 20 inches and offering a full spire of butter-yellow flowers that are small but numerous. Outside, this orchid will bloom in late spring. Inside, you might get another wave in winter.
The Reddish Calanthe
Originating from Malaysia and the Philippines, C. rubens produces pink flowers from February to May.
A native of Malaysia and the Philippines, this Preptanthe orchid flowers from February to May in its natural habitat and when kept as a houseplant. Their flower stalks average 20 inches long and feature approximately 12 pink flowers with scarlet lips. Leaves are deciduous and small with hairy undersides. C. rubens is hardy in zones 7 through 9.
Pests & Diseases
Calanthe species are known for being some of the most low-maintenance members of the orchid clan, but they are vulnerable to a handful of insects and diseases. Here’s a quick overview of their biggest issues and some ideas for addressing them.
Mites
Combat spider mites in Calanthe orchids by increasing humidity and using horticultural oils.
One of the most prominent Calanthe orchid foes, spider mites often appear when conditions are dry. Look for webbing, stippling, and brown splotches (excrement) on leaf undersides if you suspect spider mites. You may need a magnifying glass to see these tiny, spider-like insects.
To mitigate (and prevent) an infestation, boost humidity levels near your orchid and monitor closely. Horticultural oils and insecticidal soaps applied to leaf undersides are also a deterrent.
Scale & Mealybugs
Combat scale or mealybug infestations in Calanthes with alcohol swabs and soap or oil.
An attack from these insects will leave your Calanthes with chlorotic foliage (yellow and soft). Look for raised bumps or fuzzy patches near pseudobulbs or the plant’s base to indicate a possible problem with scale or mealybugs. Both populations can be decreased by swabbing leaves with diluted rubbing alcohol and discouraged with insecticidal soap or neem oil applications.
Whiteflies
Combat whiteflies in orchids with hose blasts, shaking, and horticultural oil protection.
A puff or cloud of white, tiny insects that appear when your orchids are moved or shaken indicates that whiteflies have settled in. You may also see tiny white dots on stems, leaves, and buds. Whiteflies can be discouraged with daily blasts from a hose, vigorous shaking, and a protective coat of horticultural oil.
Root Rot
Prevent root rot in Calanthe orchids by avoiding over-watering, ensuring good drainage, and monitoring closely.
This is by far the biggest threat to your orchid’s health. Invited by soil that is over-watered, overly dense, or poorly drained, root rot is not usually noticed until it’s too late. Though it begins below ground with mushy, mealy roots attacked by fungus, root rot will present above ground with yellow or brown, drooping leaves and stems.
Your Calanthe might still be saved if the issue is caught early (during division or repotting). Trim away affected roots, leaving only healthy rhizomes and root hairs in place. Dust with cinnamon or an anti-fungal product, replant in well-draining soil, water sparingly, and monitor closely.
Frequently Asked Questions
You can expect your plant to live 15 to 25 years.
Lukewarm or room-temperature water is best. Water that is too hot or too cold can stress the orchid.
Yes, but flowers will be smaller and more sporadic.
Final Thoughts
As a terrestrial, sympodial orchid, Calanthe is easy to plant, care for, and share with friends and neighbors. Remember that Calanthe orchids in your home will have different needs and cycles than those in your yard. Give the roots room to roam, keep the soil evenly moist, and monitor for stress. With a little luck (and a moderately green thumb), your Calanthe orchids should bring you joy and peace for many years to come.
