I have been growing orchids for a few years. First, California native Epipactis gigantea outdoors. I first added a terrarium for intermediate tropical orchids, then a small (4x9") greenhouse/walk-in terrarium for additional intermediate species, and a new terrarium for warm-hot species. I am particularly interested in Oberonia and Notylia.

Although I do not submit plants for judging, a Leptotes pauloensis received a Best in Show ribbon award at the Conejo Orchid Society. My exhibits at the Santa Barbara International Orchid Show received the Parma Trophy for best educational/scientific display (2013, 2014) and an EEC/AOS (90 points, 2014). I was honored with a species named after me: Dendrochilum geigeri Cootes, Cabactulan, Pimentel & M.D. De Leon, 2017.

In mid 2015, I have been joining the American Orchid Society's Resarch and Conservation Committee, and am now chairing the AOS Research Committee since 2017. I am working with the AOS Species Identification Taskforce in matters of Oberonia and Hippeophyllum. I also hold an 2013–2018 appointment as Vising Research Scholar with the Huntington Botanical Garden in San Marino, California.


Available Presentation

Oberonia under the microscopes
Oberonia is a literally and figuratively overlooked genus of orchids with minute flowers. I have become interested in this genus with some 150–300 species. An overview of the genus is provided, including many never seen before images taken with light and scanning electron microscopes. Most specimens available in the trade are misidentified; the process of checking the identification of a plant is detailed. Approaches to experimental culture of oddball orchids rounds out the presentation. This may be particularly interesting to growers who want to expand into under-appreciated orchids, or may be tempted with small research projects.
Aspects of this talk have been written up in Geiger 2014a&b, both in AOS Orchids.
The talk has been given to

  • San Fernando Valley Orchid Society 2014.
  • Southland Orchid Show 2014.
    A more academically oriented version was given in February and March, 2017, at the
  • Royal Botanical Garden, Sydney.
  • Sydney Orchid Species Society.
  • National Herbarium of Victoria, Melbourne.

    Growing orchids in a terrarium.
    Orchids require specific growing conditions. A terrarium can provide those specific conditions without the space and monetary expenditures of a full green house. The talk shows how to set-up a terrarium for orchids, and illustrates various plants that have been successfully grown in such a setting.
    The topic has been written up for the American Orchid Society Orchids magazine in 2008 and 2012.
    This talk has been given to a number of Orchid Societies, including

  • Orchid Society of Santa Barbara.
  • San Fernando Valley Orchid Society.
  • Southern California Orchid Species Society.
  • Malibu Orchid Society.
  • South Coast Orchid Society.
  • South Bay Orchid Society.
  • San Francisco Orchid Society.
  • Santa Barbara International Orchid Show (2014).
  • AOS 2016 fall meeting at the Huntington Garden, San Marino.
  • Orchid Society of New South Wales in Ermington (Feb. 2017).
  • AOS webinar, May 2017.

    Systematics 101 for orchid aficionados
    The changes in botanical names for orchids are often mystifying. I provide an understanding of how species are discovered, described, and accepted. I will also provide the audience with the understanding to read phylogenetic trees, so that one make an informed decision whether the proposed changes are sensible or not.
    The topic is being written up for a short series of publications in the Cymbidium Society of America Journal (Geiger, 2012, 2013)
    The talk has been given to the

  • Orchid Society of Santa Barbara.
  • Conejo Orchid Society.

    Imaging small orchid flowers
    As a professional microscopist and photographer who sells stock photographs I will show how to take images of small to minute orchid flowers. Techniques covered are SLR macrophotography, stereomicroscope imaging and z-stacking, and scanning electron microscopy.
    Principles of scientific photography have been written up in Geiger (2006), images have been exhibited at the Southland Orchid Show at the Huntington Garden, Pasadena, and a web article on z-stacking is available on the American Orchid Society webpage. Further articles have been published in the Orchid Digest(Geiger, 2013) and in PhotoTechniques (Geiger, 2013).
    This talk has been given at the

  • 2012 Southland Orchid Show at the Huntington Garden, Pasadena
  • Santa Barbara International Orchid Show
  • Southern California Orchid Species Society
  • Malibu Orchid Society
  • Orchid Society of Santa Barbara
  • US National Botanical Garden, Washington (DC).
  • Images have been on display at the Santa Barbara Museum of Natural History and the Smithsonian Institution.

    Orchid Publications

    • Geiger, D. L. 2016. Studies in Oberonia 1: Oberonia maxima and its new synonyms. ORCHIDS/Lindleyana section 85: 390–395.
    • Geiger, D. L. 2015. Book Review Lin & Wang, 2014: The wild orchids of Taiwan. Orchid Digest 79: 226.
    • Geiger, D. L. 2015. Book Review Parsons & Gerritsen, 2013. Compendium of Miniature Orchid Species. Orchid Digest 79(3): 117.
    • Geiger. D. L. 2014. Oberonia: the microscopist's delight. Orchids83(9): 558–563.
    • Geiger, D. L. 2014. Adventures in misidentified orchids. Orchids 83(1): 174–176. pdf
    • Geiger, D. L. 2014. Book Review Wood et al. 2011. Orchids of Mount Kinambalu. Orchid Digest.
    • Geiger, D. L. 2014. Book Review Kyte et al. 2013. Plant from Test Tubes: An Introduction to Micro-Propagation. Orchid Digest.
    • Geiger, D. L. 2013. Book Review Cootes, J. 2011. Philippine Native Orchid Species. Orchid Digest 77: 7.
    • Geiger, D. L. 2013. Imaging small orchid flowers using visible light. Orchid Digest 77: 112–123. pdf
    • Geiger, D. L. 2013. Considerations and limits of z-stacking in macrophotography. PhotoTechniques Sept/Oct. 2013: 34–36. pdf
    • Geiger, D. L. 2013. Systematics 101 for orchid aficionados. Part 2—Phylogenetics. Cymbidium Society of America Journal 13(1): 35–45.
    • Geiger, D. L. 2012. Orchids under glass. A custom terrarium with bells and whistles. Orchids 81(1): 32–43. pdf (late proofs, not final)
    • Geiger, D. L. 2012. Systematics 101 for orchid aficionados. Part 1 Species descriptions. Cymbidium Society of America Journal 12(3): 34–40.
    • Geiger. D. L. 2011. Taking pictures of tiny orchid flowers. American Orchid Society website www.aos.org/Default.aspx?id=355 | pdf of webpage
    • Geiger, D. L. 2008. Orchids under glass. Growing and flowering orchids in a terrarium. Orchids 77: 846–853. pfd (late proofs, not final)

    Other Botanical Publications

    • Carlquist, S., B. F. Hansen, H. H. Iltis, M. E. Olson & D. L.Geiger. 2014. Forchhammeria and Stixis (Brassicales): stem and wood anatomical diversity, ecolocigal and phylogenetic significance. Aliso 31(2): 59–75. pdf
    • Geiger, D. L. 2011. Growing native bulbs from seeds. The Paintbrush Winter 2011: 6, 8.
    • Geiger, D. L. 2011. Native plants for foodies: California golden currant Ribes aureum. The Paintbrush Spring 2011: 6.
    • Geiger, D. L. 2011. Native plants for foodies: California golden currant Ribes aureum, Part II. The Paintbrush Summer 2011: 5–6.
    • Geiger, D. L., 2011. An ode to Orobanche. The Painbrush Winter 2012: 3. pdf

    Other botanical Presentations

    Propagating California Native Plants in your Backyard: for your personal use of the CNPS annual plant sale. California Native Plant Society - San Gabriel Mountains chapter, Eaton Canon Nature Center, April 2014.