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.

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.

      

Welcome Angraecoid Alliance

     This month, the Angraecums blog celebrates it's second birthday.  Over the last two years it has grown well beyond the culture of growing Angraecoids.  The blog has created questions on which the answers build upon the knowledge of a group of genera that has only been touched upon by a handful of experts and dedicated hobbyists until recently.  The Angraecoid group includes so many diverse species in widely different genera, from miniature rainforest species to vining plants to robust lithophytes that there is something for every grower to enjoy.
     It is a little understood genus and has been slow in gaining popularity with hobbyists worldwide.  The Angraecums blog is giving those hobbyists and serious growers information to help grow beautiful plants and to procue phenomenal, mystical blooms we all crave to see.  The blog has attracted so many people with that need to become better growers of this unique Angraecoideae genera.  I hope to continue adding material and information that will keep this blog fresh, exciting and full of information that will be beneficial to all who read it.
     With that all said, it is my pleasure and my honor to introduce Sarah Waddoups; the founder and creator of the Angraecoid Alliance.  In coming months, Sarah and I are hoping to form a solid collaboration dealing with Conservation, Education and Research within the Angraecoideae genera.   We hope to promote awareness within the plant group, and to improve information sharing, as well as access to growers and vendors who have plants to offer. I would like to welcome Sarah!

Sarah Waddoups and Angraecum rutenbergianumon Mt. Ibity, Madagascar, 2013

     Greetings fellow Angraecoid orchid lovers!

     Hi, my name is Sarah and I'm an Angraecoid addict!

     I've grown orchids for more than 10 years and Angraecoids are a particular passion.  My collection is about 850 plants, of which more than half are Angraecoid species and hybrids.  I love the elegance of the flowers with their star-shaped blooms and long spurs.  And the fragrance is heavenly.

     In December of 2013, I spoke about Angraecoid conservation at the International Orchid Conservation Congress' meeting in Isle de la Reunion.  And being that close to Madagascar, I couldn't resist.  So all told, I spent three weeks of orchid hunting (with my camera) in Isle de la Reunion and Madagascar.  While I photographed other orchid genera, you'd be correct to suspect I was really looking for any and all Angraecoids.

Angraecum rutenbergianum, Madagascar

     As you most likely know, the habitat for Angraecoid orchids is threatened in Madagascar and tropical Africa.  The more I researched, the bleaker the future seemed.  Rather than assume that habitat loss and threats to species could not be reduced, I started to consider possible solutions.  As a result, The Angraecoid Alliance was created  in 2012.  The purpose of the Alliance is to promote conservation in-situ, increase the number of rare species cultivated ex-situ and educate growers and the public alike about the need for conservation.

 Angraecum expansum, Isle de la Reunion

     Ex-situ conservation:  Members of the Alliance are actively working to improve and create ex-situ populations of rare and/or threatened species of Angraecoid orchids.  Unfortunately, habitat destruction is rampant and ex-situ conservation may be the only way some species will survive.  The Alliance's conservation populations are established using plants that are already in cultivation (so no additional plants need to be removed from the remaining populations in-situ).  Alliance members donate pollen, set pods on their plants or contribute flasking services to propagate these rare Angraecoids.

Angraecum cucullatum, Isle de la Reunion

     In-situ conservation:  The Angraecoid Alliance is also exploring the possibility of creating a free-trade nursery in Madagascar.  This is a complicated endeavor that will take some time to establish.  The objective is to connect the free-trade nursery with nearby habitat in need of conservation.  The nursery and conservation area could provide employment for local people and provide an alternative to "tavy" framing where land is burned for agriculture.  Further, the world-wide demand for these orchids could be supplied via seed-grown plants.

     Angraecum magdalenae, Madagascar

     New members are always welcome.  Annual dues are $10.  You can become a member and follow the Angraecoid Alliance's efforts at www.angraecoids.org .  

     Follow the Alliance's blog at http://angraecoids.blogspot.com/ and like us on facebook at www.facebook.com/www.angraecoids.org . 

     You can always contact me and the Alliance directly at angraecoids@gmail.com .

Angraecum Memoria George Kennedy

     The seed parent of Angraecum eburneum ssp. giryamae and the pollen parent Angraecum comorense produces Angraecum Memoria George Kennedy.  The plant was registered officially in 1981.  In my opinion it is one of the easier Angraecum hybrids to grow.  With that said, why does it seem I have kept my fingers crossed from the day I received my first plants?  These are the first non-miniature Angraecums that I am growing in 100% red lava rock (pieces range in size from 1/2 inch [1.3cm] to 3/4 inch [2cm].  Over the last 6 months, the plants have grown very well with one presently in bloom and the other three starting to spike.

Angcm. Memoria George Kennedy (new root development)

     The image above shows one of the plant's root systems developing at the base of the plant.  The size of the lava rock will give ample drainage, room for air movement and plenty of space for the root system to grow within the pot.  I do have one plant in an 8 inch basket with other non organic material as well as the lava rock and the root system on that plants has already grown out through the slats.  SPECIAL NOTE: I water as often as I can with rain water to wash away the salts that may build up on the coarse lava rock.
     Although both of the parents are a very strong growing epiphytes, mounted plants need plenty of water during the hot months of late spring through early fall.  These mounted plants would need to be watered twice a day.  Being in shallow pots with a somewhat coarse medium, they are watered once every two days for at least 6 months and that watering is cut back to once every three to four days when temperatures do start to drop into the seventies and even the upper sixties.  (read the August 29, 2013 post "LAVA ROCK as a potting medium... PROS and CONS" to see the possible advantages to using the lava rock).

     With the parent Angcm. eburneum ssp. giryamae having a stem that can reach over 3.25 feet (1m) in height and Angcm. comorense barely reaching a height of 12 inches (30cm), Angcm. Memoria George Kennedy should grow to a height between the two.  The four plants that I am presently growing have stems that average about 4 inches (10cm) and are blooming for the first time or getting ready to.  My thinking or hope at any rate is that they won't grow much taller than 18 inches (45cm).

 First sign of developing inflorescence.

Six weeks growth.

First time blooming inflorescence with 6 buds.

     Development of the inflorescence took about 5 months to reach a point where the buds did start to appear.  I am currently keeping track of the other three plants to confirm these timelines.

     As stated earlier, the potted plants as well as the one in a basket are watered every two days from late April into mid October (6 months with daytime temperatures at 80 degrees or above with three of those months in the low to mid 90s).  A balanced fertilizer of 20-20-20 is added to the water once a week.  I have not yet added any time release material to the plants.  Once every 21 to 28 days I treat the plants with a systemic fungicide; slternating every other month between Thyomil and Dithane45.  I spray the entire plant concentrating on the under sides of the leaves and also make sure that the fungicide gets into the pot so that the root system is treated.

     Two of the plants receive a couple of hours of direct morning sunlight and then receive 35% spackled light throughout the remainder of the day as do the other two plants (2000 - 3000 fc).  They are grown in an open arbor and have a constant cross breeze 24/7.  If winter temperatures where to drop below 55 degrees for more than one night, the plants are moved inside or the arbor would be wrapped to protect from the cold. 

Angrarecum Memoria George Kennedy

     Please keep in mind that I grow my orchids in the sub-tropical to tropical climate of South Florida.  This Angraecum will do well in a intermediate to warm growing greenhouse.

Growing Aerangis Species & Hybrids

     Over the last thirteen years growing Angraecoids I have learned that when something works well, don't change it.  But; I also want to know what my parameters are.  Then of course I try to push the envelop by experimenting with different cultures.  Giving my presentations to various societies, I usually talk about Angraecoids that are relatively easy to grow for the beginner.  Gain some confidence and then start thinking about plants that may take a bit more understanding to grow them into fantastic specimens.
     Over the last two years I have posted articles on three Aerangis (Aergs. articulata, Aergs. biloba and Aergs citrata); of which I would consider easy to grow.  This post will deal with several species that I consider easier to grow than others.  As you will see, the culture of many of these plants can be very similar and some with a wide range of culture parameters/variables.  Whether it be a species or a hybrid, cultures can be similar.

Image 1 - Aerangis Mire (Aergs. ellisii X Aergs. verdickii)

 

     First thing that you should keep in mind is the individual plant's natural habitat.  Take the time to do a bit of research.  Having a basic understanding of the plant's requirements should prevent severe mistakes.  Talk to someone who is growing the plant at the present time and pick their brain.  Learning about a plant's climate, including annual monthly rainfall totals and seasonal temperatures; what is it growing on and the type of light it receives at various times of the year should put you in the proper place. 

     The cultures that I talk about in this post are the cultures I use to grow my Aerangis.  I will make comments regarding the cultures that should be considered in cooler/different climates compared to here in South Florida.  These should be looked at as guidelines or starting points.  What works for me may be different for you.

     There are usually about seventy Aerangis species; but it is not uncommon that a plant or two does get reclassified.  Plant size can range from a near non-existent stem to a stem that can reach a height of 31 inches (80cm) in cultivation (Aergs. ellisii, the seed parent of Aergs. Mire in Image 1).  My present Aerangis collection contains Aergs. hyaloides, a stem that would barely be 1 inch (2cm) to the lengthy Aergs. articulata with a stem that can reach 12 inches (30cm).  There are numerous other Aerangis in the collection at various lengths.

 

 Image 2 - Aergs. articulata, Aergs. biloba & Aergs. citrata

 

     All Aerangis as other plants have a wet and a dry season.  These seasons may vary in length depending upon location.  During the wet season, usually the active growing season, many of these plants will flourish quite rapidly.  Aergs. articulata, mystacidii, kotschyana, X primulina and somalensis to name of few of mine will grow considerably fast being exposed to moisture all day and can handle being damp during the evening.  Here in South Florida, the rainy season is heavy and the plants take advantage of the large amounts of water.  Late spring into early fall, temperatures can be in the upper 80s to mid 90s daily.  My mounted Aerangis are watered 2 - 3 times a day and often misted very late in the afternoon.  Roots that are attached to the mount as well as the aerial roots will dry out by the air movement that surrounds them (Image 3).  They are then watered again with this process being a daily regiment as long as the temperatures stay high and the plant is actively growing.

     This much water can start to cause an issue with fungus.  Watch for any brown or black spots on the leaves.  When temperatures do begin to drop, plants will still need moisture.  The combination of moisture and cooler temps, fungus can rear its ugly head rather quickly.  My collection is treated on a monthly basis with a systemic fungicide.  I alternate between Thyomil and Dithane 45 every two - three months, keeping a spray bottle of Physan 20 (a topical fungicide) handily available.

 

                                                            Image 3 - Aerangis articulata

 

     Many of the Aerangis can be grown under lights, although they are usually some of the smaller variety such as Aergs. citrata, decaryana, fastuosa, modesta, mystacidii, hyaloides and luteo-alba var. rhodosticta to name a few.  While under lights, these Aerangis should receive about the same amount of water but you must make sure that the root systems are receiving a fair amount of air movement.  When seasonal temperatures begin to drop and active growing has slowed down considerably, watering should be cut back.  Do not let the plants stay dry for extended lengths of time.  If you start seeing wrinkled or withered roots; they are not getting near enough water.  Water them at least twice a week.

     For those that are growing them on window sills or on tables next to windows during the colder winter months; have your plants setting in or very near humidity trays.  When your home or apartment is being heated during the cold winters of the north, humidity drops much lower than the plant is exposed to in its natural habitat.  For small mounted plants, arrange the plants on some sort of a stand so that it is in very close proximity or directly above the tray.  Small pots can be set in the tray resting on glass marbles or anything that can keep the pot above the water line.      

      As mentioned, the majority of my Aerangis collection is mounted.  Some of the larger Aerangis can be grown in pots or baskets as long as a coarse medium is used to allow for fast drainage, good air flow and room for root development.  A good sampling of larger plants for potting would include Aergs. articulata, cryptodon, ellisii, fuscata and kotschyana.  Because these plants produce somewhat pendulous inflorescence, they can be hung on a slight angle so that the spikes can drop over the edge of the pot and flower freely.

 

Image 4 - Aergs. decaryana X Aergs. mystacidii & Aergs. mystacidii

 

     Flower shapes of the various Aerangis species that I grow will range in shape from a flock of birds in flight to various star shapes and sizes to unusual fan shapes (Images 2 & 4).  Their sizes vary from flowers that are less than a half an inch (8mm) wide by less than a half an inch (8mm) long and a spur that is club shaped and only 1/4 inch (6mm) long [Aergs. hyaloides] to flowers that are up to 2 3/4 inches (7.4cm) wide by 2 3/4 inches (7.4cm) long with a spur that can reach 5 - 6 inches (12.7-13cm) long [Aergs. articulata].  Colors are white while some of them may have delicate hints of green, yellow or pink at the tips of their sepals and petals.  Spurs will be white, a very pale green or a very subdued yellowish green.

     These are just a few of the Aerangis species that I am presently growing.  As stated earlier, the culture that I am currently using is what works best for me in the South Florida climate.  Do the research and ask questions and you will grow these plants successfully.  They will become wonderful specimen plants.  There will be future posts regarding Aerangis punctata culture as well as a post dealing with the flower shape of Aerangis luteo-alba var. rhodosticta.

     Don't hesitate to ask/post questions or comments to the blog!