Orchid societies around the country are gearing up for their late winter and early spring shows. One plant that always draws a crowd is Dendrobium spectabile – a naturally occurring species from Australia, Papua, and New Guinea that was discovered in 1849. Not only are the pseudo-bulbs and leaves imposing, but the flowers are some of the most unusual in the world.
Generally regarded as full grown at ten years old, this Dendrobium makes canes or pseudo-bulbs in excess of 3’ tall. A sturdy 10” -12” pot is required to hold this monstrosity. Its size and weight compares only to standard Cymbidiums.
The flowers of Dendrobium spectabile defy description. The bizarre 3” blossoms have sepals and petals which are extremely twisted - sometimes wrapping around each other and keeping the buds from opening. The colors are a blend of yellow, burgundy, and white but give the impression of a washed-out tan. The throat has a ‘hinged’ mechanism which bounces with air movement, attracting a specific pollinator in the wild. The grower can simulate this bounce by gently shaking the flower. The blooming duration is about 6 weeks and older plants can easily produce 100+ blossoms.
Fragrance is a highly coveted trait in orchids though few genera offer it. This Aussie Dendrobium’s semi-sweet aroma is strong from across the room, day or night. Even Oncidium Sharry Baby, the famous chocolate scented Dancing Lady, cannot compete with the intensity.
The culture of D. spectabile is similar to common evergreen-type Dendrobiums except that higher light is recommended. Increasing the sunlight to Vanda levels (5,000 foot candles) or slightly-filtered direct exposure will yield additional flowers. Twice a week watering and potting in fir bark works well for all Dendrobiums.
There are two other notable Australian Dendrobium species which get quite large and garnish considerable attention – D. speciosum and D. kingianum – both of which are capable of producing hundreds of blossoms. In their native country, there are entire orchid conferences devoted to these plants.
Here, in the United States, Dendrobium hybrids have been one of the most popular genera for decades. Their long sprays of colorful and long lasting flowers resonate with orchid enthusiasts who appreciate ease of growing and year-round availability. For those who want to try something a little different, Dendrobium spectabile will surely capture the imagination. Beginners are encouraged to purchase young seedlings as these are a bit easier to get home.