Jacksonville Orchid Society Oncidium sphacelatum Contest

JOS members attending the society’s 8 September General Meeting were able to select divisions of Oncidium sphacelatum donated by long time supporter Maurice Geiger of Geiger Orchids.

So what to do with the divisions? Let’s have a contest. We’ll judge in several categories with the obvious first and most being, first bloomed! We’ll also consider best grown at the September 2021 meeting as well.

Prizes? How about bragging rights? Beat up your BOD members and make your proposal for the types of recognition we should consider for this contest.

OK. Thoughts onĀ Oncidium sphacelatum.

JOS Member Joshua Jones put together an excellent You Tube video on his channel, “The Orchid Den.” See it at https://l.facebook.com/l.php?u=https%3A%2F%2Fyoutu.be%2FtlwqJDZpPcA%3Ffbclid%3DIwAR0I1niLq2g–VOG62yeilgxrBUiQJbDlzfoAtp5bHjiD0DsQMY-gbiJJtE&h=AT0uQdgjh1fEdvWCpPWvsv27DaV5Ik06g_qwCjbbbYcw69ZedZMQ0a3lZ2WXOasQgAj0yXZ8vDRJLezscPidFwi1TlZdFxTAQ6LzB8T7fYYKWvlUmAlR17LLuXsP-Az3g0JRfm6TFlJ1Hvk

Oncidium sphacelatum is one of the easier orchids to grow and is one of those that easily runs toward the ‘large’ size. Jay Phal of the Internet Orchid Species Photo Encyclopedia (see http://www.orchidspecies.com/oncsphacelatum.htm) provides the following description:

This is a giant sized, hot to warm growing epiphyte and occasional lithophyte with compressed, oblong pseudobulbs carrying 2 to 3, linear-ligulate, suberect, rigid, acute leaves found in tropical and mountain rain forests occuring in Mexico, Guatemala, Belize, El Salvador, Honduras, Nicaragua, Costa Rica and Venezuela where it is found below 1000 meters and blooms in the spring with a basal, to 6′ [180 cm] long, lateral to pendulous, short branched, purple mottled panicle arising from the leaf bearing sheaths of a mature pseudobulb that has triangular bracts and carrying showy, weakly fragrant flowers.

In plain English – This orchid will grow well in the Jacksonville area. However, during the winter you will have to protect it from cold weather as in its native environment it does not typically see temperatures much below about 60F.

The late Charles Baker offered guidance on growing this orchid as synopsized below.

Light – As bright as possible short of burning the foliage without exposing to direct mid-day sun.
Temperature – Jacksonville easily gets hotter than recommended for this orchid, but with air movement and shading is easily grown. I grew a large specimen by hanging under one of my trees without issue. Again, your biggest problem is keeping it no colder than about 60F during winter. Having said that, I kept mine in my garage where temperatures got to about 45F and it didn’t hurt the orchid at all.
Water – water actively from early spring to late October. Reduce the water for 2-3 months in the Winter – Early Spring.
Media – media should be fast draining but should retain some moisture. Oncidium sphacelatum can also be mounted but care must be taken to ensure it does not dry out in our hot summers.
Flowering – The key is lots of light – right up to the verge of burning the orchid leaves.

In reviewing Josh’s video on Oncidium sphacelatum, you’ll note he potted his in a clay pot with water retentive media. I chose a different approach and mounted mine in a basket with a surround of osmunda. Who’s will be first to flower? We’ll know next year!