Masdevallia Culture: An Interview with Dale Borders

by Dale Borders and Marianna Max

Dale Borders grows Orchids on the Oregon coast in a small town called Bandon. Dale grows mostly species - about 1300 different species in c. 250 genera. Dale’s greenhouse is built in 3 sections. The first section is a large intermediate growing area built around a pond and containing a second story mezzanine where he grows high light plants. There is a smaller warm room to the west for Vandas and other warm growers. The cool room is equipped with a 21/2 ton air conditioner and is located in a small step-down area to the east of the main structure. In addition to the growing areas, there is a south facing structure with access to an enclosed yard for Dale’s breeding pair of African Spur Thigh tortoises. Dale has been growing orchids continuously for 30 years. He and his wife Deni farm cranberries (Bandon is one of the few areas in the country that is ideal for cranberry bogs). Besides orchid growing, Dale loves taking photos of his orchids using an Olympus C2500L model digital camera. He shares these photos with friends via the internet.

The following is from an email interview with Dale about one of is favorite genera.

Max: What would you say was the most critical aspect of Masdevallia culture?

Dale: Temperature. Although many genera of orchids are tolerant of mal-cultural conditions, Masdevallias are generally less tolerant. Certainly the fact that Masdevallias possess no moisture storing organs other than their leaves, commits them to being more vulnerable to even short periods of other than habitat temperatures.

Several species of Masdevallia are widespread and locally abundant, but habitat diversity is an exception in this genus. Most species of Masdevallia are endemic to highly endemic; some species are found in only a single isolated valley or canyon. Considering the fecundity of orchids and the great number of seed produced, one can only presume that the plants are singularly intolerant of conditions other than that experienced in the habitat. Although other habitat circumstances are variable, it's my belief that temperature conditions are most variable within a given geographic area and plants in cultivation at my home seem to confirm my belief that even a few degrees Fahrenheit can make a large difference in a plant's health.

Humidity is also an important aspect of Masdevallia culture; but considering that relative humidity is a function of temperature, humidity becomes a corollary of temperature management in cultivation. If temperature is managed, humidity is usually appropriate, or easily managed and augmented.

Diurnal temperature range is nearly as important as maximum and minimum temperatures. Extreme daytime temperatures are detrimental to a Masdevallia as transpiration often exceeds the plants ability to take water from the media. Plants subjected to extreme high temperatures for great lengths of time, whether diurnally or during a hot period, expend more energy staying alive than is available from reserves; the result is usually death, or at the very least, shed leaves. Allowing the plant to experience cool nighttime temperatures partially expiates the effects of high daytime temperatures and allows the plant to 'recover' and carry on the business of photosynthesis.

Max: So the best way to be successful growing Masdevallias is to know the temperatures you can provide and only choose plants that naturally do well at those temperatures. What kind of media, fertilizer and water do you use for your Masdevallias?

Dale: The type of medium a person uses for Masdevallia must be tailored to watering habits of the grower. The most important aspect of potting media for Masdevallias is that it drain quickly, yet retain some moisture for periods concomitant with watering frequency. Increasingly, sterile sphagnum moss is being used. Sphagnum moss should be packed as loosely as possible, as in a very short time (depending on watering frequency) it can become tightly packed and unsuitable. Another drawback of sphagnum moss is that it tends to deteriorate quickly if fertilizer is applied. However, Masdevallias are light 'feeders' and in some cases, Masdevallias can remain in sphagnum moss for two years or more if fertilizing is greatly reduced. Some of the best Masdevallias I've seen were growing in live sphagnum moss.

Masdevallias require very little fertilizer and will usually suffer if provided fertilizer as for other commonly grown genera. Frequent and strong fertilizer applications will result in weak new growths, damaged roots, and browning of leaf tips; the ultimate result will be death of the plant if frequent applications of fertilizer are continued. Most Masdevallias come from regions with high rainfall and most species are typically found growing on horizontal branches rather than the bole of large trees. Even with prodigious rainfall, very little organic 'debris nutrient' is washed to the plants on a horizontal habitat; conversely, plants growing on the bole of large trees benefit from the 'trickled down' nutrients of the entire tree canopy above the plant. There are also many terrestrial Masdevallias, but Tropical soils are typically nutrient poor.

Water quality is exceedingly important for successful cultivation of Masdevallias. As noted above, fertilizers can be damaging; water with a high Parts Per Million (PPM) ratio of Total Dissolved Solids (TDS) are equally detrimental. My Masdevallias are watered with surface water of 60 PPM/TDS year 'round and I've not found it necessary to manipulate my water quality. Certainly, if symptoms of 'fertilizer poisoning' as mentioned above become evident, scrutiny of water quality is probably necessary.

Max: Are all Masdevallias shade loving or do some like bright light and how can you tell?

Dale: All Masdevallias will usually grow well when cultivated in low light, but many will fail to bloom if not provided with relatively bright light as suitable for Cattleyas. Most of the members of the section Coriaceae require bright light to bloom. Most of the members of this section have evolved to habitats that are characterized as 'scrubby', and are typically high altitude, low precipitation habitats. As Masdevallias possess no water storing organs such as pseudobulbs, members of the section Coriaceae are characterized by thick succulent leaves. Additionally, Masdevallias that inhabit dry areas usually have roots that are coarse and covered with a heavy layer of velamen. The flowers of section Coriaceae are typically brownish mottled variously with red, beige, and purple. Flowers are heavy textured and often fetid. Coriaceous means 'leathery'.

Photos by Dale Borders of Masdevallias he’s grown on the Oregon Coast.