Bullish on Stanhopeas

Stanhopea hernandezii

For a long time I thought of Stanhopea hernandezii as a sort of junior sized version of Stanhopea tigrina, that mastodon of the stanhopeas. Both give the impression of a massive cranium and formidable tusks. But it wasn't until this summer when we flowered both species simultaneously that I was able to compare them side by side.

Stanhopea tigrina

In profile, it's easy to see that the the bottom of the hypochile is rounded like a bowl in hernandezii, but flattened in tigrina.

Stanhopea tigrina, a second color form

Stanhopea hernandezii, dorsal view

The horns are round in cross section and slender in hernandezii, but flattened and broad near the base in tigrina.

Stanhopea tigrina, dorsal view

Stanhopea tigrina, dorsal view

Stanhopea hernandezii, lip and column

Notice the striking difference in the columns of the two species: hernandezii's narrow column compared with tigrina's broadly winged column.

Stanhopea tigrina, lip and column

Stanhopea tigrina, lip and column

Stanhopea hernandezii, lip

With the column removed you can see how much broader the epichile is in tigrina than in hernandezii.

Stanhopea tigrina, lip

Stanhopea tigrina, lip

Stanhopea hernandezii, lip in ventral view

Stanhopea tigrina, lip in ventral view

Stanhopea tigrina, lip in ventral view

Stanhopea hernandezii, column

Stanhopea tigrina, column

Stanhopea tigrina, column

Stanhopea hernandezii and tigrina are both endemic to Mexico. S. hernandezii occurs on the southwestern slopes of the Mexican plateau at about 1,600 to 2,000 meters elevation in the states of Morelos, Mexico and Michoacan. I can't find referennce to a specific pollinator for hernandezii. The largest fragrance components measured by Gerlach (in Lankesteriana 2010) are cinnamyl acetate (64%) and benzyl acetate (11%).

Stanhopea tigrina is known from  the eastern slopes of the plateau at about 1200 to 1800 meters in the states of Tamaulipas, Hidalgo, Puebla and Vera Cruz. Its pollinator is Euglossa viridissima. The chocolate fragrance described so often in the literature (but which I cannot discern in our plants) derives from the combination of phenylethyl-acetate, a primary component of the fragrance, and vanilline, one of the secondary components, according to Rudolf Jenny.

Our S. hernandezii, which we received from a commercial nursery as S. ecornuta, flowered in August and probably won't be on display again until next summer. On the other hand, we have quite a few S. tigrina in our collection. The flowers only last about three days, but it's definitely worth stopping by to try to catch them when they flower in August and September. They are magnificent.

Stanhopea costaricensis

July is just a little early for stanhopeas here. It will be another month before the flooodgates open. In the meantime, we had a magnificent Stanhopea costaricensis in flower in the Orchid Display House last week. The fragrance was just wonderful, with a hint of vanilla.

Our Stanhopea costaricensis  has deep red splashes of varying sizes on the lip and column and some fascinating leopard spots on the petals and sepals.

It's flower isn't quite as big as the really big boys- Stanhopea tigrina, embreei and platyceras, but big enough that I had to back the camera way up in order to get the entire flower and pedicel in the frame.

Seen from above, the elongated lip has a diamond shaped hypochile.

The column has prominent wings.

Stanhopea costaricensis grows as an epiphyte in Central America between 500 and 1500 meters elevation. It grow without any problems in our intermediate greenhouse (60º night minimum) in 60% shade. And it makes an impressive specimen sized (12") basket with outstandingly fragrant flowers.

Stanhopea platyceras

It's not very often that we have two different clones of the spectacular Stanhopea platyceras flowering in close proximity, so this was a good opportunity for comparison. It's easy to forget how variable some species can be. ABG 20041565 has a long narrow hypochile that is relatively lightly spotted.

The second clone, ABG 20140724, has a stouter hypochile with spots that have almost coalesced into a deep purple (intensified in this flower after day three). Platyceras means 'broad flat horns', a characteristic that is more striking in the second clone.

Stanhopea platyceras flowers are big (4 inches across) and almost everyone who sees them stops for a second look. They seemed to be the most photographed orchids in the Orchid Center when they flowered. Stanhopea platyceras is endemic to Colombia, according to Rudolf Jenny, where it grows at 1000 to 1500 meters elevation. We grow our plants in an intermediate greenhouse in 70% shade. I'm happy to report two capsules developing on 20041565, the result of selfings. One capsule will go to the lab for seedling production, the other will be photographed.

Stanhopea nicaraguensis

Stanhopea nicaraguensis 19901127 is a especially valuable plant in our orchid collection because it is a division of the holotype -the specimen used by the author to create a formal description for the original publication.

The plant was originally collected in 1975 by John Atwood from the Peñas Blancos mountains in Jinotega department, Nicaragua. It flowered in June of 1990 at the University of Florida-Gainesville and we received a division as Stanhopea ruckeri. Another division of the UF-Gainesville plant was sent to Münich Botanical Garden and flowered in September of 2008. Günter Gerlach described it in Orchideenjournal No. 4, 2009, giving it the new name Stanhopea nicaraguensis.

According to Gerlach, this may be the only clone currently in cultivation.

Stanhopea nicaraguensis grows in montane rainforests in the departments of Jinotega and Matagalpa, Nicaragua at elevations between 600 and 1000 meters. The fragrance is 65% 1,8-cineole (think Vick's VapoRub), according to a fragrance analysis performed by Whitten and Williams in 1992.

We're thrilled to have this rare orchid in our collection. And I am happy to report that we've got a nice fat capsule developing, which I expect will ripen in spring of 2016.

Stanhopea embreei

Our Stanhopea embreei produces some impressive flowers -carrot colored and nearly four inches across. The inflorescence is magnificent. And the fragrance is pure methyl cinnamate -like fresh strawberries. S. embreei has almost the same fragrance as two closely related species, S. jenischiana and S. frymirei, with whom it shares a pollinator. The three species are separated by geography and elevation, according to Rudolf Jenny in his Stanhopea monograph in the journal Casesiana.

The lip and column after the petals and sepals have been removed

Lip minus column. The hypochile (top of the hourglass) is broader in embreei than in jenichiana

The ventral surface of the lip

The column has broad wings

Stanhopea embreei grows as an epiphyte at intermediate elevations on the western slopes of the Andes in Ecuador and Peru.

Stanhopea wardii

As the summer Stanhopea season winds down, I'm continuing to photograph our collection for our image library. They are beautiful. The shiny black eyespots are wardii's calling card -most (but not all) plants have them. This accession of Stanhopea wardii has a burnt orange and yellow hypochile. It smells strongly of cineole (camphor).

Above, I've removed the sepals and petals, leaving just the broadly winged column, lip and pedicel.

The lip and pedicel after I've removed the column.

Stanhopea wardii ranges south of Honduras, from Nicaragua, Costa Rica and Panama to Colombia and Venezuela, where it grows as an epiphyte at 800 to 1600 meters elevation in humid cloud forests -a good candidate for an intermediate (60º night minimum) greenhouse.

Stanhopea connata

Stanhopea connata ABG# 1993-2450

Not every Stanhopea smells like a pastry shop. Poor Stanhopea connata. It's the one Stanhopea that can clear a room.

Dorsal view of Stanhopea connata ABG# 1993-2450

While most stanhopeas have fragrances delectable enough to eat, Stanhopea connata exudes cresole and indole. Cresole is the fragrance compound associated with coal tar (think freshly poured asphalt). And indole has a fragrance described in botanical literature as fecal. I was not, to be honest, in a hurry to have a closed door photo session with Stanhopea connata.

Front view of Stanhopea connata

And that's too bad! Look at that face, with the bold tiger stripes and spots. I was completely charmed. Charmed and overwhelmed, actually.

Dorsal view of the lip and column with sepals and lateral petals removed 

Of course, it doesn't matter one bit what I think of the fragrance. The fragrance is all about attracting a pollinator. And it's kind of cool to think that there are fragrance-collecting bee species in the tropics who are mad for asphalt and cow dung.

Dorsal view of the lip without the column

My photo shoot with S. connata lasted about an hour. Over time, the cresole seemed to diminish and the indole began to assert itself. But by the end I hardly noticed. What a handsome plant this is. The images will be stored in ABG's image library.

Ventral view of the lip

Stanhopea connata grows as an epiphyte along the eastern cordillera in Peru, Colombia and Ecuador. It is pollinated by Eulaema speciosa.

Ventral view of the column

How to Repot Stanhopea

September and October are Stanhopea repotting season for us. Every grower has their own repotting technique, but I thought you might want to take a look behind the scenes at ours.

Orchids that are flourishing don't generally appreciate the root disturbance that repotting can inflict. Stanhopeas are no exception. We repot when: 1) The plant has overgrown the pot; 2) The medium needs to be replaced, either because it has deteriorated -after about two years- or because it is inappropriate for our growing conditions; or  3) The plant is in trouble. Signs of trouble include desiccated leaves and shriveled or rotting pseudobulbs.

The stanhopeas above, which we received last week from Andy's Orchids, fall into the second category. Andy grows his stanhopeas in a medium that works well for him, but turns to mush in our greenhouses during our hot & humid summers.

We repot our orchids when the new roots and shoots appear. For most stanhopeas, that's in late summer and early fall. In the photo above, you can see the new shoot on the Stanhopea graveolens in the foreground. Now is the time!

Because our plants are far from the main potting bench in the headhouse, I set up a temporary potting bench in our back-up greenhouse. It's just a pair of plastic sawhorses supporting a 5' rectangle of plywood. Potting materials include net baskets, razor blades and one of our favorite orchid media, a mixture of long-fibered premium moss and coarse tree fern fiber. The plants were watered the previous day in order to soften the potting medium.

1. To remove the plant, invert the pot and tap the rim against the edge of the potting bench.

2. Gently remove the old medium around the exterior of the root mass, small bits at a time so as to not break the new roots.

To remove the old medium from the center of the root mass, hold the plant by the pseudobulbs (not by the roots!), and wash the roots gently under running water. Remove about three quarters of the medium. It's not necessary to remove every bit unless you see rotting tissue. Rotting roots and pseudobulbs are easy to see after washing and can be removed with a razor blade.

3. Choose a pot size based on the size of the root mass. For a plant this size, we want a pot about an inch wider than the root mass on all sides. And, for a Stanhopea, choose a basket with openings that allow the downward-growing spikes to emerge from the root mass.