How to Grow and Care For Christmas Star Orchids

Orchids are an incredibly wide-ranging and fascinating group of plants. They grow on every continent except Antarctica and comprise the largest plant family, with more than 25,000 species in close to 850 genera. Moreover, orchids are one of the most popular houseplants, and scientists discover hundreds more species every year.

They get a reputation for being difficult. However, with some knowledge of the way they grow, their care becomes much clearer. In fact, they prefer a bit of neglect. Let’s take a look at one of the rarer orchids called ‘Christmas Star,’ and talk about how to grow it in your home.

Angraecum sesquipedale ‘Christmas Star Orchid’ Overview

Plant Type Perennial epiphyte Family Orchidaceae Subfamily Epidendroideae Genus Angraecum	Species Sesquipedale Native Area Madagascar Exposure Bright Indirect Light Height Up to 40” Hardiness Zone 10-12	Watering Requirements Moderate Pests & Diseases Mealybugs, root rot, bacterial spot Maintenance Low to moderate Soil Type Loose, large particles, well-drained

What Is It?

The ‘Christmas Star’ orchid goes by several names. The shape of its flowers explains its nicknames “Christmas Star” and “Star of Bethlehem.” Perhaps the most intriguing is the moniker “Darwin’s Orchid,” a name which comes from the famous evolutionist’s fascination with the species. 

It was the extra-long nectar spur that drew him to this species, and he surmised that there must be a pollinator with a similarly long tongue. Years after his death, the discovery of the sphinx moth made his conjecture a certainty. This moth, indeed, has a long proboscis and is responsible for pollinating this wonderful plant.

Characteristics

What sets this species apart from others is not its lovely star-shaped blooms, though they are beautiful. It is the long spur that hangs from the back of the flowers. It can be up to 45 cm long, but it holds nectar only in the bottom inch or two. 

The striking white flowers are large, star-shaped, and lightly fragrant during the day. In the evening, they emit a much stronger scent that is musky with hints of gardenia and vanilla. This fragrance attracts its sole pollinator, the sphinx moth (Xanthopan morganii praedicta). They bloom between May and November from high up in the trees, where they make their home as epiphytes. In Europe, they bloom in December and January, which is why many associate them with Christmas.

Epiphytic plants grow non-parasitically on trees, taking in the light from under a canopy. This one is a tropical rainforest plant and prefers a lot of moisture. Occasionally, orchids in this species are lithophytic, growing from cracks in rocks, but this is less common. 

The ‘Christmas Star’ orchid is monopodial. It grows constantly upward on a central rhizome. Flowers form on tall stems that grow from the base, where the leaves meet the roots. The leaves are dark green and characterized by a bilobed tip.

Native Area

The ‘Christmas Star’ orchid is endemic to Madagascar and is not found in the wild in any other part of the world. This plant grows in lowland forests, near the forest edge, in trees with fewer leaves, where it can receive a lot of air circulation and light. 

How to Grow

This particular orchid lives up to its reputation for being fussy. It’s not a great beginner orchid, but if you have success with cattleyas, this one has similar needs. Because it is rarer and, as a result, more expensive, I recommend starting out with a cattleya for anyone who is just starting out. It is uncommon to find this species in private collections, but it’s not impossible. 

Light

‘Christmas Star’ is a fairly high-light species, similar, as I mentioned, to cattleyas. It typically grows in trees with sparse foliage, where it receives more light than most orchids. Some direct sun early in the day will not harm it, but keep it out of direct sun in the afternoon when the light is more intense and hotter. 

Filtered light for most of the day is ideal. You can place this in a window with privacy glass or behind a sheer curtain in a brightly lit window. An excess of green growth with no flowers for a year indicates that it’s not getting enough light. Faded leaves that may have white patches indicate too much direct exposure. 

Water

The more light it gets, the more water this plant will need. Under ideal circumstances, if you grow it indoors, you should water it once a week. Outdoors, it will need more frequent watering. An under-watered specimen will have wrinkled leaves that make it limp or wilted. 

Overwatering is deadly to orchids, which have exposed roots in the wild. This means that they get a lot of air circulation and dry out quickly. They also lack the organic material found in soil, which can foster fungus when they remain wet for long periods. 

When the soil stays wet, the roots stay wet, and they can develop root rot. Root rot manifests in yellowing leaves and a soft, yellowing crown. By the time it affects the crown, it is typically over for that plant. 

I prefer to water by immersion, dunking the pot into a sink full of water. This makes it easier to fertilize and allows the roots to absorb all they need. If you use the pour-over method, be sure to keep water out of the crown and tops of the leaves, as this can rot the plant.

Soil

The soil is another important factor in this orchid’s health. It should mimic the natural environment and have excellent drainage to maintain good air circulation around its roots. A commercial orchid bark mix is ideal for this plant. If you prefer to mix your own potting media, two parts bark combined with one part charcoal and one part vermiculite or pumice is a good place to start. 

Temperature and Humidity

Like most tropical types, this is a warm-climate orchid. It prefers warm days with temperatures between 65 and 85°F (18-29°C). At night, slightly cooler temperatures are best—between 55 and 65°F (13-18°C) is perfect. Don’t leave this one outdoors when the seasons change and cool off. It is not cold-tolerant.

‘Christmas Star’ is also a high-humidity species, as most tropical species share this characteristic. The ideal humidity level for this orchid is between 50% and 70%, which can be difficult to achieve in drier climates. Keep this orchid in a bathroom where showers happen regularly, or use a humidifier to raise the moisture level around it. 

Fertilizing

Orchids like a lot of fertilizer, and this one is no exception.  This species tends to have a nearly constant growing season, so you can fertilize year-round. Use an orchid fertilizer or any balanced formula that is liquid soluble. 

Fertilize every time you water. This seems like a lot, but much of the fertilizer washes out. Once per month, give the roots a long rinse with clean water to wash out any buildup. 

Maintenance

Orchids don’t require regular pruning. The only thing you need to cut off is the spent flower stalk. You should wait until it is brown so the plant can re-absorb the nutrients it contains. Cut it just above the first node closest to the base. 

Once per year, typically right before blooming, it may lose the oldest set of leaves. This is no cause for alarm, and there is no need to cut them off. Just allow the plant to drop them as it would in the wild. 

Propagation

The best way to propagate ‘Christmas Star’ orchids is by division. You can grow them from seeds, but it takes a long time and is complicated. Unless you have the equipment and proper environment, I would skip it. It’s easy to divide them. It’s best to do it when you re-pot. Never do this while the orchid is in bloom.

Monopodial orchids also produce keikis, which are babies that they send out on stems that grow their own roots. Wait until there are several of these, and your orchid has outgrown its pot, to propagate them. Then it’s time to remove these, and pot them on their own. They will drain nutrients from the parent plant. 

Common Problems

Orchids have some issues to watch out for, mostly related to overwatering, but there are also some pests to watch for. 

Pests

Mealybugs are the most common insect that bothers orchids. These waxy little pests like to attach to the fleshy leaves and suck out the sweet sap. They can drain it of nutrients and reduce growth and flowering. They also leave behind excrement called honeydew. This sticky stuff is a breeding ground for black sooty mold, which inhibits photosynthesis. 

Their waxy coating makes mealy bugs difficult to treat with common products like neem or horticultural oils. However, they have many natural predators, so when I see them, I move the plant outdoors for a few days, and that usually does the trick. 

Alternatively, you can use an alcohol-soaked Q-tip or cotton pad. The alcohol breaks down that waxy outer coating and kills the insects. Rinse any residue off right after wiping away the insects, as it can desiccate the foliage. 

Diseases

Root rot is the most common orchid killer, and it’s usually caused by over-watering. If you suspect root rot, you’ll want to re-pot immediately and remove all rotted tissue so that the condition doesn’t worsen. Once it reaches the crown and the majority of tissue rots, it’s typically fatal. 

Bacterial leaf spot can also be an issue. The cause is splashing water from an infected plant to an uninfected one. The lesions will initially look like water spots and then turn black and necrotic. This is not usually fatal, but those leaves need removal. Removing them prevents the spread of disease to that orchid and its neighbors.