Angraecum leonis

Thursday, April 17, 2014

Angraecoids of South Africa

       Over the last fourteen years, I have had the opportunity to meet numerous people from all parts of the globe that have a passion for Angraecoids.  Meeting some in person and others via the internet.  People such as Joyce Stewart, Johan Hermans and Bob Campbell; authors of "Angraecoid Orchids, Species from the African Region".  Sarah Waddoups, the founder and CEO of the Angraecoid Alliance.  An organization dedicated to the in-situ and ex-situ conservation of Angraecoid genera.  Lisa Hillerman, the youngest daughter of Fred Hillerman, author of "An Introduction to the Cultivated Angraecoid Orchids of Madagascar"; she has shared so much of her father's knowledge and photographs from his trips to Madagascar in the 1970s.  Craig Morell, the horticulturalist from Pinecrest Gardens in Miami, Florida; not only did I spark his interest in Angracoids; but the knowledge I picked up from him is priceless.  Alan Koch and Robert Fuchs, respected growers and accredited American Orchid Society (AOS) judges.  The list goes on and on.
       At this time, I'd like to introduce to my readers, Etienne Bosman (I met Etienne via this blog and the Facebook page).  An orchid hobbyist that is very good at what he does and resides in South Africa being surrounded by the Angraecoid genera.  The plants that are sought after for culture in our green houses in just about all corners of the world.  This guest post will hopefully be the first in a series both he and I will be working on throughout the year.  Sharing knowledge of both the natural habitats and cultures from the southern and the northern hemispheres.  Please welcome Etienne Bosman.

       "And I have thought, that as orchids are universally acknowledged to reank amongst the most singular and most modified forms in the vegetable kingdom, the facts to be presently given might lead some observers to look more curiously into the habitats of our several native species."  
                                                                     Charles Darwin  

       And so I did,, looking more curiously into the habitats of our several native species.  I must say it did take some time to do just that.  Unlike most of the Angraecoid growers around the world; I am fortunate enough to be living in an area that numerous Angraecoids call home.

Etienne Bosman

       Just 350 km north from Pretoria in the Limpopo Province, South Africa; lays the Magoebaskloof Pass.  One of the great classic passes of Limpopo and one of the most scenic passes in the country.  This pass takes you from the High Veld (Escarpment) to the Low Veld traveling in a northeastern direction; descending 446 vertical meters from a summit of 1400 m ASL.


        Magoebaskloof is part of the Limpopo Mistbelt forest; and very often, due to thick mist, the indigenous forest will not be readily visible while driving through the pass.Mistbelt forests are confined to higher altitude, soll, southern slopes of mountains.  This provides reduced radiation and longer lasting moisture on the forest floor.  These aspects combined with the temperate climate provides ideal growing conditions for orchids.


       The Limpopo Mistbelt covers a large area with vast geological differences, from the cool escarpment and upper mountain plateau to the warm and humid low veld.  The forest's typical landscape is undulating plateau , steep slopes, gullies and valleys comprising a total area of 19204ha (made up of state forests as well as small forest patches of private land owners).  Most of the annual rainfall varies from 1800mm at higher altitudes to 600mm at lower altitudes.  At altitudes above 1050m where mist is frequent the epiphytes rely on fog and mist which create the high humidity.

Georges Valley

       My passion for South African orchids started when I befriended Callie and joined the Wolkberg Orchid Society.  The Wolkberg Orchid Society was established in 1982, with a mere eleven members.  This was the first orchid society  ever to be established north of Pretoria.  Our society is still rather small only reaching 30 members in the last year or so.  A handful, about five, including our president Dr. Sarel Spies (who is a qualified SAOC judge), are indigenous orchid fanatics, explorers and vastly knowledgeable; properties I desire to attain. Our society president regularly encourages us to explore whenever and find whatever we can; which we do on a regular basis.  All of us know the easy to access locations that makes it handy to pop and appreciate the plants when in flower.  But we prefer the lesser known, and for us it is with great excitement to select a forest patch and go exploring and see what we could find.
       Our club has discovered species that were unknown to occur in our area, also finding new locations of species thought to be rare.  In my early days I would point at almost anything and shout "ORCHID!" which would draw laughter and jest; but always quickly followed with educated corrections.  It took some time for my eyes to adjust to spotting the orchids I was so eagerly seeking, but I never became discouraged.  At one stage my orchid hunting became so obsessed that my insurance company wanted to increase my insurance rates for risky driving.  We would be driving and I would spot something in my peripheral vision, I would instantly slam on the brakes with little or no regard to what might be coming up from the rear (they have eyes and can see me braking, can't they?).  My partner would always illicit and untrustfully respond, "I'll just be a minute" while fleeing the vehicle with my binoculars and machete; which is always at hand.


       Within a 150km radius in which we live, we have found eighteen Angraecoid species.  In the upper mountain plateaus, you can find Angcm. pussilum, Angcm. sacciferum, Angcm. chamaeanthus, Mystacidium gracile, Mystacidium flanaganii, Mystacidium venosum, Mystacidium braybonae and Margelliantha caffa.  These can often be spotted by their conspicuous roots; which are more visible than the plant itself.  When not in flower, some of the mentioned species can be difficult to differentiate from each other.  When found in large numbers together, (or even just a single plant in flower) they still tend to take your breath away.  Angraecum conchiferum tends to grow in clumps on the bigger branches.  When in flower the tiny flowers hang in mid-air away from the plant with the spurs dangling in the breezes.

  Mystacidium braybonae

       In the warmer riverine forests and the more humid low veld, Jumellea walleri can be found high-up in the canopies, often forming huge clumps, more than often growing together with Acampe pachyglossa.  At a much lower level you will find Aerangis somalensis and Aerangis mystacidii in deep shade.  The distinction between Aerangis somalensis and Aerangis mystacidii is sometimes debated; but they are regarded as two distinct species.  Aerangis verdickii grows in hot valleys in exposed conditions that can withstand long periods without rain; to which it has adapted through very fleshy leaves and very thick roots.  You will also find Tridactyle tricuspis and Tridactyle bicaudate; Cytorchis arcuate and Cytorchis praetermissa.  Cytorchis arcuate often grows lithophytically as well as an epiphyte; it is more widely distributed and more adaptable; but always in subtropical forest patches.

Callie Wagenaar

       Lastly, the emblem of the 21st World Orchid Conference held here in South Africa... Angraecum stella africae; which is threatened with extinction in South Africa.  Only two locations are known, both in Limpopo, with speculation about more locations making the rounds.  It needs serious protection.
       All of the orchids I have mentioned are on the red list.  The red list is the brain-work of the Threatened Species Programme of the South African National Biodiversity Institute (SANBI).  The Threatened Species Programme is one of the continent's largest collaborative conservation projects to date.  South Africa has become the first mega-diverse county to fully assess the status of its "entire" flora.

Dr. Sarel Spies and Callie Wagenaar investigating a clump of orchids in full sun.

       Over the years we have noticed how locations on private, corporate and state owned properties are getting less and less populated with Angraecoids as well as other orchids due to several serious factors.  Over collection by hobbyist growers and poachers, leaving only the top unreachable branches with mature plants.  Habitat loss due to irreversible conversion of natural vegetation for infrastructure development, urban cultivation and timber plantations.  Invasive alien plants out competing indigenous plant species.  Demographic factors like species that are threatened as a result of high risk population dynamics such as small population size, poor breeding success, male-female ratios and changes in species dynamics indicating species that are threatened as a result of disturbances of the natural interactions of native species such as the loss of pollinators.

Aerangis verdickii

       A permit from the Department of Economic Development and the Environment and Tourism offices in the region of concern must be obtained if one wants to collect whole plants or even just a part thereof out of its natural habitat.  Another permit must be obtained from the Department of Agriculture if any virgin land (including forests) are to be transformed.  As far as I am concerned none of these are enforced adequately due to lack of manpower and just because of the huge task involved in doing so.  Some people do hold the opinion that some of the forests are over protected and have lost their vitality; that a large proportion of the trees are just standing there, with no orchid growth and that only the more shade-tolerant species persist and suggests that they need some controlled limited interference to flourish.
       There is some confusion amongst land owners and officials of what "virgin land" is and suggest that the policy must be further refined.  This confusion leads to landowners that may become unwilling to collaborate in conservation of indigenous tree species and forest development on their land because of the potential to be constrained in their actions in the future.  The only way to protect the indigenous orchids of South Africa (and the world) is through education.  Educating the public and landowners, with the hopes of grating conservation-conscious and to protect rare plants on their land.  The Botanical Society of South Africa (BotSoc), has championed the cause of wildflower protection and conservation.  Through conservationand educational programmes, projects and initiatives via branches around the country.

Angraecum conchiferum

       Sadly, many people think that the indigenous orchids would look better in there greenhouse than in nature.  It has happened various times that we take visitors to the locations of rare plants and six months later; upon a return visit to the same location we would find nothing left.  For this reason alone, we are forced to keep these locations a very closely guarded secret.  For me personally, there is nothing as beautiful as to observe the indigenous species in their natural habitat.  I want to share that thought with fellow orchid lovers.

Article References:
* Field Guide to the Orchids of Northern South Africa and Swaziland, by Douglas McMurtry, Lourens
   Grobler, Jolisa Grobler and Shane Burns
* Angraecoid Orchids, Species from the African Region, by Joyce Stewart, Johan Hermans and Bob
* Dr. Coert J. Geldenhuys, Forst Ecologist, Extraordinary Associate Professor in Forest Science at 
   Stellenbosch University
* Dr. Bronwyn Egan, Curator, Larry Leach Herbarium at University of Limpopo
* Dr. Sarel Spies, Wolkberg Orchid Society
* The South African National Biodiversity Institute (SANBI)
* The Botanical Society of South Africa (BotSoc)
* Photographs by Herbert Starker and Etienne Bosman

Monday, April 7, 2014

Oeniella polystachys

Oeoniella polystachys

         In February of 2013, I added a post dealing with the culture I use to grow Oeoniella polystachys. Over the last month and a half, I have received numerous emails from hobbyists and growers regarding this genus. Some of the questions I fielded dealt with culture on a more specific level.  Rather than do an update on the Oeoniella post, I decided to rewrite it and bring it forward on the blog.
 Oeoniella polystachys is one of the few Angraecoids that inhabits the lowlands of eastern Madagascar itself, as well as all three island chains surrounding Madagascar: the Comoro Islands west of the northern tip of Madagascar, the Mascarene Islands to the east of Madagascar, and the Seychelles Islands to the north and northeast of Madagascar. Oenla. polystachys is epiphytic, and grows primarily on trees not much higher than sea level.
Sub-tropical/tropical South Florida is a perfect climate for this species. In northern, cooler climates, it should do well in a warm greenhouse or grow area.  Oenla. polystachys is a robust grower and will develop year round; it does not have a dormant/rest period.  The plant does well throughout the wet season (May through September), and can handle the drier season unless temperatures fall below 45 degrees for several nights.  Here in South Florida, I keep all of my Angraecoids in an open air arbor and move them indoors if the temperatures stay at or below 45 degrees for three or four consecutive nights (the extent of the winter season throughout the last four years in South Florida).  I have been fortunate that I’ve only moved them in for a three day period in the last four years.
In its natural habitat, Oenla. polystachys grows in high humidity and a warm climate.  It can usually be found on trees that allow more light through due to a thinner canopy.  In culture, I grow my plants mounted to tree fern totems, which gives the aerial root system the opportunity to grab hold and grow into the mounting material as the plant gains height.
In culture, I have not seen any plant above twenty inches (50cm); however, in-situ they can grow as high as twenty four inches (60cm).  The plant has been known to put out basal keikeis and start to branch prior to its first blooming. It can become quite a specimen in just a few years.

Inflorescence and root separation
As Oenla. polystachys starts to gain height, the aerial root system continues to grow and will develop roots to within 3 – 6 inches (7.5-10cm) of the crown.  Roots are borne opposite the leaf axils, usually at each leaf.  The inflorescence also develops opposite the leaf axil.  Once blooms have waned and the plant continues to grow, roots will then develop in the same place.  Roots can start while the inflorescence is in flower.
         The root system at the base of the plant has been known to drastically slow, if not stop developing completely; there lies the importance of mounting the plant to a material that will give it the opportunity to stabilize itself.  South Florida’s high humidity is not enough moisture; the plants are watered every morning while temperatures are 75 degrees, and twice a day once the low to mid 80s arrive (usually early April).  As we go into the summer and early fall months, the plants are also misted about an hour prior to sunset, allowing just enough time for the plants to dry off in the warm summer breezes.
Inflorescences usually start to develop in late September or early October.  They take about four months to gain length (6 – 10 inches [15-25cm]) and then just a few weeks for the buds to completely develop prior to opening.  Mature plants that are well taken care of can produce 4 – 7 inflorescences, each bearing 12 – 16 flowers.  These flowers are heavily fragrant just after dusk and into the middle of the evening;  flower size ranges from slightly under an inch to  a little over an inch and a half (2-4cm).  The sepals and petals are thin, pointed and usually have their pointed tips curled slightly in.
 With the active growing season being year round, I do not drop off the watering cycle unless temperatures fall below 60 degrees; I will then water every 2 or 3 days instead of every day.  Fertilizer is once every week to ten days and the fungicide treatment remains every 30 days.
 The amount of light that Onela. polystachys is given varies slightly during the summer months compared to the winter months.  During the summer months, it receives direct morning sunlight until about 12pm and will then receive about 25 percent filtered light until late afternoon.  As fall and early winter arrive, the plant will receive some very late direct sunlight until dusk.  Avoid direct mid-day sun throughout the year.  I have seen plant leaves burn in just a few days.  The leaf color should be a vibrant green, although there can be very little visual difference if the light is backed off.
 For a beginner hobbyist, Oenla. polystachys is an easy Angraecoid to start growing.  As with any orchid species or hybrid, give the plant it’s requirements and it will grace you with beautiful blooms every year.  You should be able to find the plant for sale at many of the orchid shows that take place throughout the year.  For anyone with additional questions, leave your questions or comments in the comment section just below in this post.

Friday, April 4, 2014

Death by Dehydration

             One of the common ways of killing your orchids is not watering them properly; watering properly takes some time to learn when you’re a beginning hobbyist (as well as some of us that have the experience to know better).  But what may have happened if you are sure that you knew what you were doing?
Whether you had your hand in it or there was another circumstance, we all know orchids die without the right amount of water.
            Two issues that have come to my attention via the Angraecums blog may shine some light on the subject.  An Angcm. sesquipedale and an Angcm. Crestwood both started dropping their leaves from the bottom of the stem until the leaf drop eventually reached the crown.  Both plants were mature specimens producing beautiful flowers on a yearly basis.
           Orchids and other types of plants will start to show signs of stress when being dehydrated.  Leaves usually show the biggest sign; they begin to wrinkle or shrivel, pseudo bulbs will thin out and not look as plump and stems/canes can begin to bend over and not hold up as they should.  These signs point towards lack of moisture.  Either not enough water is making it to the root system or there are no longer enough roots to supply the plant with that moisture.
            Seeing these signs, many of us will automatically start giving the plant more water.  However, what if we see no sign of improvement in a short period of time and the plant continues to deteriorate; let’s assume the root system has failed.

                        Signs of severe root rot                                       Shriveled aerial root 

            I looked closely at this problem with an Angcm. sesquipedale recently and found that the root system was  totally dead.  The vellum material that covers the actual root had completely disappeared, what material did exist was barely a shell and much of it was black.  This black on the vellum material indicated severe root rot.  Somehow, the plant was getting to much water and was constantly wet even though the potting material allowed for fast drainage and the pot itself had plenty of openings for good air movement (which in itself would cause issues if the air around the plant was still).  The bottom line is that the roots were always very wet and eventually rotted.  Aerial roots were present but not enough of them to salvage the plant.  Those roots shriveled and did not supply the plant with the necessary moisture (sort of a catch-22).
            The second plant I looked was an Angcm. Crestwood.  Leaves were turning yellow and then dropping off starting at the bottom of the stem.  The plant had been staked holding it upright; and with the stem as thick as it was, the stake shouldn’t have been needed.  The initial problem was that wind had toppled the plant breaking the stem completely through just under the medium in which it was potted.  The severed stem prevented the roots from passing moisture up into the plant causing a fast and steady dehydration.
              Last fallen leaves from Angcm. Crestwood                        Break at bottom of stem

             Both of the above issues were caused by damage to the root system.  By carefully monitoring the watering cycle of the first plant may have prevented the plant from dehydration.  Protecting large showy plants such as the Angcm. Crestwood from strong winds would have prevented the plant from being blown over which caused the break in the stem.  Understanding how plants eventually die will make us better growers.  Growing orchids successfully means learning how to control all of the variables; and issues with watering them is just one small piece of a complex puzzle.