Trichocentrum microchilum

Week 67: August 23, 2021

Trichocentrum microchilum

New candidate for this week is Trichocentrum microchilum.

Trichocentrum microchilum (Bateman ex Lindl.) M.WChase & N.H.Williams, 2001 is accepted species by WCSP, Kew. This species is native to Mexico, Guatemala, El Salvador and Honduras. This species has several synonyms: Oncidium microchilum Bateman ex Lindl. (1840), Lophiaris microchila Senghas (1997) and Lophiarella microchila Szlach., Mytnik & Romowicz (2006).

Previous Awards:

There is no AOS awards for Trichocentrum microchilum.

However, there are 2 AOS awards for Oncidium microchilum (AM 80 pts in 1969 and CCM 84 pts in 2000).

Interesting that this species newer received any botanical awards (accepted species or synonyms).


Trichocentrum microchilum has 370 flowers on 5 inflorescences up to 81 cm. The plant grown in 6 inches clay pot in course bark.

Flower Measurements:

NS H - 1.6 cm; NS V - 2.0 cm;

Dorsal Sep. W - 0.8 cm; Dorsal Sep. L - 0.8 cm;

Petal W - 0.2 cm; Petals L - 0.6 cm;

Lat/Sepal W - 0.6 cm; Lat/Sepal L - 1.0 cm;

Lip/Pouch W - 1.0 cm; Lip/Pouch L - 0.5 cm.

Judges' Comments

Al Messina (Accredited Judge, Northeast Judging Center)

Beautifully grown, virtually immaculate example of a rarely seen species occupying what appears to be a brand new greenhouse which suffers poor water quality (judging by the massive degree of leaf tip necrosis in an adjoining plant). If the candidate was indeed grown in the same location as the afflicted plant with the same water supply, it appears to have weathered the storm quite well. In my opinion, all species presented to AOS judging should have at least one passage through the SITF(Species Identification Task Force) to bless the species with its imprimatur so that no doubt about its species veracity will be in question. And so a CHM would be in order. A marginal CCM of perhaps 80 points might also be considered recognizing its superior culture.

Kristen Mason (Accredited Judge, Cincinnati Judging Center)

Thank you for this interesting Trichocentrum. I love the color of the lip and the display on the inflorescence. Comparing this plant to the awarded clones, this entry has smaller flowers and less flowers. There is also some cupping of the dorsal, waviness on the petals and reflexing at the tip of the lip that are not present in examples of this species found in the literature and online. Based on the botanical description and specimens available thru KEW and other published papers, this entry appears to be what it is identified as. While awarded twice thru AOS, it also has 4 awards thru the German orchid judging system (2013-2018) and 1 thru TOGA in 2009. Because there are already awards to this species in AOS (and thus not eligible for CBR) and there are no variances observed in this flower that would warrant a CHM, I would pass on this entry.

Deborah Bodei (Associate Judge, Northeast Judging Center)

Trichocentrum microchilum


The grower should be commended for good culture. The plant is attractive and clean.

There isn’t anything about the flower in form, color or size that would make me pursue a flower award, so I am looking primarily at culture. This plant is smaller, growing in a smaller pot (about half the size) than the awarded. Presentation of the inflorescences is nice but under-flowered in comparison. I am unable to get to 80 points on the scoring for culture.


The plant is very nicely grown; however, I would not nominate on this flowering.

Thank you,


Tom Mirenda (Accredited Judge, Hawaii Judging Center)

A terrific species admirably grown and flowered. Flowers look to be fuller and more colorful than is typical for the species

Plant is unblemished, extremely turgid and vigorous While the previous awards to Oncidium microchilum also apply to this plant,,,,

I think three awards are possible and reasonable here

  • CCM for its excellent culture and blooming….I think 85+ pts is appropriate

  • CHM as it is clearly a desirable species with horticultural merit

  • And a merit award of some kind…probably an HCC or low AM as the flowers are certainly above average for the species

Tom Mirenda

Sergey Skoropad (Associate Judge, Northeast Judging Center)

Trichocentrum microchilum.

Lovely Central American species which can grow to a large specimens.

Interesting, that prior to August 2021 this species received only 2 awards (in 1969 and 2000, both under Oncidium microchilum) and newer received any botanical awards (CBR or CHM).

Our candidate has 370 flowers on 5 inflorescences and grown in 6 inches pot.

Number of the flowers is less then indicated in previous awards. However, this is a smaller plant, grown in smaller pot with less number of pseudobulb/leaves. Based on photos and video I can see that plant is in a very good condition. Presentation of the flowers is pretty good. I found that flowers are more colorful than previously awarded.

I think grower should be awarded for taking care of this rare species and I can see CCM 80-81 pts.

Because this species never been properly described and newer went through SITF before, I would like to nominate for CHM. However, question is - if species already recognized by AOS and received flower and cultural awards, is still possible to receive botanical award?



Lia Amato (Student Judge, Società Felsinea di Orchidofilia, Bologna, Italy)

Very well-grown plant that makes a fine display with its five erect inflorescences bearing 370 flowers, elegantly carried on the stems; the mahogany color of the sepals and petals in beautiful contrast with the red and white color of the lip. The graceful shape of the well-proportioned flowers and the typical appearance of the “mule ear” leaves, large and numerous in a color that ranges from green to violet, give this orchid elegance and strength. I would certainly give a Certificate of Cultural Merit.

Ettore di Giovanni (Student Judge, Società Felsinea di Orchidofilia, Bologna, Italy)

Beautiful plant, very well grown, well branched, with well arranged and healthy leaves. Long stems well erect, robust, bearing 370 flowers of size, shape and color typical of the species and well proportioned. I would definitely grant it a Certificate of Cultural Merit.

Filippo Pilloni (Associate Judge, Società Felsinea di Orchidofilia, Bologna, Italy)

Perfectly cultivated plant with a flowering well above the norm for the number of stems and open flowers. The shape and intensity of the color are also above the average of the species.

The stems and flowers are perfectly presented in a pleasant and harmonious union with the plant.

For these reasons I propose a Certificate of Cultural Merit of 86-87 for the exceptional quality and cultivation of the plant.

Alejandro Capriles (Accredited Judge, Società Felsinea di Orchidofilia, Bologna, Italy, retired AOS Judge)

Exceptionally grown plant bearing 370 flowers on 5 beautifully erect inflorescences. The mustard-yellow petals and sepals almost completely suffused dark mahogany present an elegant contrast with the white and yellow lip blotched cerise red. The flower shape and size are average for the species but the exceptional cultivation deserves nothing less than a Certificate of Cultural Merit.

Exhibitor - Bill Stender, NJ

Virtual Award Description

Three hundred seventy flowers well-held on five erect, multibranched inflorescences to 81 cm, emanating from 5 of 22 single-leafed, green pseudobulbs; leaves elliptic, green, margins light purple, carried on an very clean, 35-cm wide by 85-cm tall plant growing in a 15-cm clay pot in course bark; dorsal sepal markedly cupped, yellow-green, heavily overlaid chestnut; lateral sepals ovate, yellow-green, heavily overlaid chestnut; petals yellow-green, heavily overlaid chestnut, mildly undulated; lip trilobed, white, midlobe heavily overlaid maroon, side lobes white, kris-shape, acuminate apex, complex anther cap trilobed, white, light yellow apically; substance firm, texture glossy.

Grower's Advice

This plant was purchased from the Northeast AOS judges' auction several years ago and it is a division from a plant at the Brooklyn Botanical Gardens. When I posted it to a private group of orchid growers that I chat with, one of the participants is Greg Griffis from Longwood Gardens, PA and he was very excited to see the plant because all of the Longwood divisions were virused, so one day I hope to donate a division to Longwood. Maybe Brooklyn has another plant that they could send over to Longwood for a trade?

I grow this high and bright and make sure it will fully dry out before nightfall. It is definitely time to repot and hope to grow it into a bigger specimen in a few years.

As a side note to Al Messina, I grow exclusively with rain water, but yes I have been struggling with that Bulbophyllum for several years and I suspect it needs to be repotted. It is sphagnum at the core of that net pot and I suspect is rotted witch is cause the necrosis of the leaves.