Dendrobium Anosmum

If you’re looking for an orchid that combines stunning beauty with an incredible perfume, look no further. The dendrobium anosmum is a true gem for any plant lover, known for its cascading stems and a scent that can fill an entire room.

This exotic orchid, often called the “Unscented Dendrobium” (which is quite misleading!), is a rewarding grower. With the right care, it will thrive and produce its magnificent blooms year after year. Let’s get into everything you need to know to succeed with this special plant.

Native to Southeast Asia, this orchid is an epiphyte. In the wild, it grows on tree branches, not in soil. Its long, pendulous canes (pseudobulbs) can reach several feet in length, creating a dramatic display. When in bloom, the flowers appear directly from the nodes along these canes.

The fragrance is its most famous feature. Often described as a mix of raspberry, hyacinth, and vanilla, the scent is strongest in the morning. It’s not subtle—a single spike in bloom can perfume an entire sunroom or patio.

Why Choose This Orchid?

There are many reasons this species is so popular among collectors:

Incredible Fragrance: Few orchids offer such a powerful and pleasant aroma.
Architectural Form: The long, leafy canes are attractive even when not in flower.
Relatively Easy Care: Once you understand its cycle, it’s quite adaptable.
Spectacular Bloom Display: A mature plant covered in flowers is a breathtaking sight.

Ideal Growing Conditions

Mimicking its natural habitat is the key to a healthy plant. Here’s what it needs:

Light Requirements

This dendrobium loves bright, indirect light. Think of the dappled sunlight under a forest canopy.

A south or east-facing window with some sheer shading is perfect.
Leaves should be a medium green color. Dark green means too little light; yellowing can mean too much.
It can tolerate some morning sun, but avoid harsh afternoon rays that can scorch the leaves.

Temperature & Humidity

It prefers a distinct seasonal change. This is crucial for triggering blooms.

Spring/Summer (Growing Season): Warm (70-85°F / 21-29°C) with high humidity (60-80%).
Fall/Winter (Resting/Dormant Season): Cooler and drier. Aim for 50-60°F (10-15°C) at night if possible. Daytime temps can be in the 60s-70s°F.
Use a humidity tray or a room humidifier, especially during dry winter months indoors.

Air Circulation

Good air movement is non-negotiable. Stagnant air invites fungal and bacterial disease.

A small, oscillating fan set on low in the growing area works wonders.
This mimics the breezy conditions in its native tree habitats.

Planting and Potting Media

Because it’s an epiphyte, it needs a very open, fast-draining mix. Traditional potting soil will suffocate and rot its roots.

Excellent potting media choices include:

Medium-grade fir bark
Sphagnum moss (often mixed with bark for moisture retention)
Coconut husk chips
Tree fern fiber
A mix of perlite and charcoal for added drainage

Repot only when the media breaks down (every 2-3 years) or when the plant has badly outgrown its pot. The best time is just as new roots begin to emerge at the base of a new cane.

Watering and Fertilizing Schedule

Your watering routine must change with the seasons. This is the most common area where growers make mistakes.

During the Growing Season (Spring-Summer)

Water frequently, allowing the media to approach dryness but not become bone-dry.
Fertilize weekly with a balanced orchid fertilizer (like 20-20-20), but diluted to 1/4 or 1/2 strength.
Flush the pot with plain water monthly to prevent fertilizer salt buildup.

During the Dormant Season (Fall-Winter)

Significantly reduce watering. For many, a light misting or sip of water every 2-3 weeks is enough.
The canes may shrivel slightly—this is normal.
Stop fertilizing completely during this rest period. The plant is not actively growing.

Step-by-Step Guide to Encouraging Blooms

If your plant is healthy but refuses to flower, it’s likely missing its seasonal cue. Follow these steps:

Ensure a Strong Growing Season: Give it plenty of light, water, and fertilizer from spring through late summer. This builds up energy in the canes.
Provide a Cool, Dry Rest: In late fall, reduce temperatures if you can. Move it to a cooler room or a sheltered porch. Drastically cut back on watering.
Look for Flower Buds: After 6-8 weeks of rest, tiny buds (called “sheaths”) should appear at the nodes along the leafless canes.
Resume Care Gradually: Once buds are clearly formed, slowly return to normal watering and move it back to its warmer, brighter spot. Avoid repotting at this stage.

Common Problems and Solutions

Even experienced gardeners face issues. Here’s how to troubleshoot:

Yellowing Leaves

Lower, older leaves: Natural shedding, especially before dormancy.
New or many leaves: Could be overwatering, insufficient light, or a nutrient deficiency.

No Flowers

The #1 cause is not giving it a proper cool, dry winter rest with reduced watering.
Insufficient light during the growing season is another common culprit.

Wrinkled Canes

Some wrinkling during dormancy is normal.
Severe or persistent wrinkling during the growth season means the plant is dehydrated. Check if roots are healthy (firm and white/green) or rotten (brown and mushy).

Pests

Watch for scale, mealybugs, and spider mites. Treat early with insecticidal soap or neem oil, ensuring good coverage. Isolate affected plants to prevent spreading.

Propagation Methods

You can propagate your dendrobium anosmum in a couple ways:

Keikis: These are baby plantlets that sometimes form on the nodes of the canes. When they have several roots 2-3 inches long, you can carefully detach and pot them separately.
Division: When repotting a very large plant, you can divide it. Ensure each division has at least 3-4 mature canes and some new growth. Use a sterile tool to cut the rhizome.

FAQ Section

How often does Dendrobium anosmum bloom?

Typically once per year, in the spring. The flowers can last for several weeks, especially if kept in moderate conditions.

Can I grow the ‘Unscented Dendrobium’ outdoors?

Yes, if you live in a climate with mild winters (USDA zones 10-11). In temperate zones, you can grow it outside in dappled shade during the warm summer months. Remember to bring it inside before nighttime temperatures drop below 50°F (10°C).

Why are my Dendrobium anosmum flowers falling off?

Premature flower drop (bud blast) is usually caused by a sudden change in environment. This includes drastic temperature shifts, a big move in location, or underwatering during bud development. Try to keep its environment stable once buds appear.

What’s the difference between Den. anosmum and Den. superbum?

They are actually the same species! Dendrobium superbum is an older, synonym name that you might still see on some tags. The correct, accepted name is Dendrobium anosmum.

Should I cut the old canes after flowering?

No! Do not cut off the old, leafless canes. They act as a nutrient and water reserve for the plant and can produce flowers again in future seasons. Only remove a cane if it is completely brown, dried out, and dead.

With its intoxicating fragrance and elegant form, the dendrobium anosmum is a standout in any orchid collection. Success comes from understanding and respecting its natural cycle of growth and rest. Pay attention to its seasonal needs, provide bright light and good air, and you’ll be rewarded with a spectacular floral show. Remember, patience is key—sometimes a plant needs to settle in for a year or two before it hits its full blooming stride. Give it the conditions it loves, and this exotic orchid will become a cherished part of your home for many years.