Angraecums

Angraecums
Angraecum Longidale

Monday, February 25, 2013

Angraecum leonis (Size Identifies)

     In August of 2012, the initial post regarding Angraecum leonis was published in the blog.  Since then, I have received numerous emails and questions dealing with the two varieties of Angcm. leonis.  The questions center around the distinctive differences between Angcm. leonis from Madagascar and Angcm. leonis from the Comoro Islands.  This post will give a visual description of the two varieties along with a review of the culture that I use to grow these phenomenal plants.
     As stated in the original post, the Angcm. leonis from Madagascar is the smaller of the two varieties.  It grows at the very northern tip of Madagascar at about sea level where the annual rainfall is nothing compared to the amount of rain that the variety from the Comoro Islands receives.  The amount of rainfall has a big play into the size of the two varieties. 
     With less rainfall, the Madagascar version is usually half the size.  The leaves are shorter but are very fleshy.  The thickness of each leave can be 2 - 2 1/2 times as thick.  The leaves hold moisture due to the fact they receive less rain.  As I have shown with other Angraecums, when the plants are exposed to more moisture, they have a tendency to become larger plants.  When they are not, they adapt to survive.

Angcm. leonis (Madagascar version) the thick fleshy leave
                                      retains what moisture it can get due to the dry climate.
 
     The leaves of the Madagascar version are about half the size on a mature plant compared to the version from the Comoro Islands.
 
Angcm. leonis (Madagascar version) the longest leaf on this
                                      mature plant is less than half the size of a leaf from the
                                                               Comoro Islands version.
 
Angcm. leonis (Comoro Islands version) the leaves on each
side of the plant are just about the same length.  Can reach
an overall combined width of 14 plus inches (35 cm) on a
well established mature specimen.
 
     Both versions of Angraecum leonis will do well mounted to a cork or a tree fern slab.  During the warmest part of the growing season, the plants must be watered daily with an additional misting later in the afternoon.  If you see that there are wrinkles forming in the leaves, hydrate the plant several times a day until the wrinkles start to disappear.  If the plants have been mounted with any moss around their base, be sure to thoroughly soak the material (it will dry out quickly during the summer heat and with any breeze blowing).
     Either version can be potted or placed in baskets with a fast drain medium.  The roots of plants that have been placed in pots can develop root rot if not allowed to partially dry.  Very often when the leaves start to show wrinkles, it can also spell out the fact that the roots have rotted and the plant is not getting sufficient moisture even if you're watering on a regular basis. 
     Keep an eye on potted plants!  In sub-tropical and tropical climates, it is best to use a non-organic material when potting or placing plants in baskets.  This very warm and humid climate will brake down the organic mediums very quickly forcing you to change the medium more frequently.  This does not bode well for the root systems.
     Flowers of the two versions of Angraecum leonis is also another tell tale sign as to the identity of the plant.  The Madagascar version of Angcm. leonis is only about 1 - 1 1/2 inches (3-4cm) wide and about 1 1/2 - 2 inches (4-5cm) high with a nectary/spur about 2 3/4 - 4 inches (7-10cm) long.  The Comoro Islands version is about 2 1/4 - 3 inches (6-9cm) wide and about 3 inches (8cm) high with a nectary/spur of about 3 1/2 inches (9cm) long.  Both versions are scented and can last up to four weeks if the plants are not exposed to harsh weather while in bloom.
     One last visual point of difference between the two Angcm. leonis versions is the shape or the bends of the nectary/spur.  The nectary of the Comoro Islands version goes back behind the flower draws down and then comes forward underneath the flower.  The Madagascar version will go behind the flower, draw down and as it comes forward reverse again to form the letter 'S'.  These are common traits but keep a mental note that not everything is written in stone.
 
The Comoro version on the left while the Madagascar version
is on the right showing the letter 'S' in a developing bud of
Angraecum leonis.
 
     No matter what version you are growing, you will be very pleased once the plant starts producing flowers on a yearly basis. 

Wednesday, February 6, 2013

Oeoniella polystachys

     Oeoniella polystachys is one of the few Angraecoids that inhabit all three island chains that surround Madagascar; the Comoro Islands west of the northern tip of Madagascar, the Mascarene Islands to the east of Madagascar and the Seychelle Islands to the north and northeast of Madagascar as well as inhabiting the lowlands of eastern Madagascar itself.  An epiphyte that grows primarily on trees not much higher than sea level.

Oeoniella polystachys
 
     The main reason I started growing Oenla. polystachys is because of the sub-tropical growing conditions here in South Florida.  It thrives on large amounts of moisture and has a very short rest period.  I started with plants in pots and mounted to tree-fern totems.  In just a few short months, I eventually mounted all of the plants due to the aerial roots coming from the plant as it grows.  It is almost always in a growing phase, no matter the time of year.  As you can see in the image below; it was potted as a seedling and already in bloom for the first time.  After learning more of the plants characteristics and realizing that it climbs somewhat, I thought it best to mount.
 
Oenla. polystachys first time blooming
 
     Mounted to a tree-fern totem, Oeoniella polystachys will eventually start attaching itself to the totem.  Aerial roots will form up the length of the plant usually to within 4 inches (10cm) from the top.  It is best to have a bed of moss at the base to help hold moisture until the aerial roots have taken hold.  The roots form just above the old inflorescence or opposite the leaf axils.  Most of those roots will find the totem material and grab hold.  Although I eventually mounted the plants that I had put in pots, doesn't mean you shouldn't grow them that way.  My suggestion is that the pots be at least 5 - 6 inches (13-15cm) wide and a medium that would allow fast drainage and giving the roots the air that they need.  The stems of the plants have the capability to grow to 24 inches (60cm) tall but are very seldom seen that high.  To keep the plant from dropping over or becoming pendant, they should be staked or supported in a manner to keep them erect.  Oenla. polystachys can start to branch heavily and keeping it erect will give the added support necessary.
     Plants that are mounted should be watered daily and when temps reach above the mid 80s F, they should be watered or misted a second time about two - three hours prior to sunset.  Allowing the plant ample time to dry before dark.  Plants that are potted should be watered every 2 - 3 days and when warmer temperatures arrive, mist the plant mid to late afternoon.  As stated earlier, Oenla. polystachys  has a very short rest period.  Watering should not be backed off unless temperatures drop below 70 degrees F.
     Oeoniella polystachys will do very well in a warm greenhouse in the cooler/colder parts of the northern hemisphere while mounted or potted.  If the plants are kept indoors such as a home, they should not be exposed to temperatures below 70 degrees F for any great length of time.  As long as warm temperatures are maintained, watering habits should not change.  Please note; if temperatures do lower, watering can be cut back to every other day when mounted and every 4 days while in a pot.
 
Oeoniella polystachys mounted to a tree fern totem
 
     Oenla. polystachys is capable of taking very bright light as long as it is diffused or spackled the entire day.  Most of my plants receive a fare amount of direct sunlight until about noon or mid-day.  During the hotter part of the day, mid-after to late afternoon, the light is toned down.  A bright shade or 25 percent spackled light works well.  It is imperative that a good air movement be available; if it is not, do not expose the plant to any direct sunlight, keep it in a bright shade or a spackled light.
     A mature, well nurtured plant should bloom or be in bloom twice a year; with a 2 - 4 month break in between.  The inflorescence develop at the opposite side of the leaf axils and are about 6 - 10 inches (15-25cm) long.  Each inflorescence carrying 10 - 15 flowers.  Mature plants can produce 5 - 7 spikes at one time.  The flowers range in width, 3/4 - 1.5 inches (2-4cm) across.  The spur/nectary is about 1/4 inch (.6cm) long forming at the base of the lip and tapers at the tip.  Flowers can last 3 - 4 weeks and longer if the plant is protected from harsh weather conditions and are fragrant in the early part of the evening.
 
Oeoniella polystachys
 
     My plants are fertilized every 7 days with a well rounded and balanced fertilizer year round.  They are treated every 30 days with a systemic fungicide that I switch every three months.  I am always on the lookout for signs of fungus on the bottom side of the leaves.  A wet climate for too long of a period or cooler weather can bring about fungus issues.  Keeping a quart spray bottle of a topical fungicide is a great idea.
     Oeoniella polystachys is a phenomenal plant for those that keep warm conditions year round. Like any other Angraecoid, give it what it requires and then be prepared for outstanding flowers.