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Wednesday, October 24, 2012

Angraecum eburneum ssp. giryamae


                During the early part of my presentation regarding the Angraecum Alliance, I stress the fact that many of the alliance do not do well in the blooming department if the roots are bothered or disturbed too much.  In other words, they become somewhat dormant when it comes to blooming for as long as and up to five years.  You will see this mentioned in various posts throughout the blog.  This particular post is going to address that probability in depth dealing with an Angraecum eburneum along with the culture demands of this species.
                Angraecum eburneum ssp. giryamae or Angraecum giryamae (the specific species in this post) as it is now classified as well as two other sub-species of Angcm. giryamae hail from various locations such as Madagascar, the Mascarene Islands, the Comoro Islands and East Africa; their origination depending upon the species.  They are all considered sub-tropical to tropical growers and grow in fairly moist areas as epiphytes and occasionally as lithophytes and semi-terrestrial plants.  Exception to this is Angcm. eburneum spp.  xerophilum grows in the semi-arid to arid areas of Southern Madagascar where there is a 3 – 5 month dry or dormant period during the winter months in the Southern Hemisphere (this species is discussed indirectly as one of the parents in the post “Birth of a Shooting Star”).

                                  Image 01                                      Image 02
 
Several days after giving the Angraecum presentation to one of the South Florida Orchid Societies, I received an email along with a photograph attached showing an un-named Angraecum that had grown so much that it had pushed itself out of the pot.  The plant appeared to be Angcm. giryamae and was in excellent health.  No sign of stress or any severe batches of fungus.  It had very strong leaves of green with numerous secondary plants and a few kiekies (Images #01 $ #02).
The root system was visible (and there were many), most were 3/16 – 5/16 inches (.4 - .6cm) wide.  There was also a substantial number of new roots with green tips almost 3/4 inches (2cm) long.  It is this root system that shouldn’t be disturbed.  I always explain that when potting or placing certain species of Angraecums in baskets; you should use a container that will not need to be changed later.  Let the plant grow into it!  Angraecum giryamae can reach a height of 4 – 6 feet (1.2 – 1.8m); although a plant in culture will very seldom reach a height of over 4 feet (1.2m).
            The instructions given to the plant owner were followed exactly as given.  She had a 12 inch (30cm) square by 6 inch (15cm) deep cedar basket prepared for the transfer of the plant.   The medium was a mixture of charcoal, perlite, tree fern pieces and coconut chunks that were considered to be medium size.  She very carefully used a small hammer and broke the pot up around the plant’s base root system.  She did not pull any of the broken pot pieces off of the roots.  Whatever fell off at the time of breaking the pot is what was thrown away.  Any of the old medium that was still stuck to the root system was left alone.

Image 03
 
The plant was then placed into the cedar basket and the new medium was placed into the basket around the plant.  Then very carefully working the new medium into the voids in and around the plant.  Once the plant was settled into the basket, it was watered and a systemic fungicide was used to treat the plant.  It was placed in the same area receiving the same amount of light and care has it had previously (Image #03).

             
During the summer months, the plant was watered about every three days, fertilized once a week and a systemic fungicide is used about every four weeks.  Patience now has the upper hand; will the plant lie dormant or will it bloom?
Images 04

             Late this summer, the plant starting putting out an inflorescence; a very good indication that it would bloom.  Watching it develop and finally seeing the first buds appear gave even a higher degree of hope that the re-potting of the large Angraecum was a success.  As you can see in the following image, the Angraecum giryamae successfully bloomed (Image #04).

            
Not every transfer or re-potting of a mature Angraecum will be this successful.  Root systems are used by this genera as any other.  Supply the plant with moisture and stability.  But, the root systems are much more sensitive.  If the roots are disturbed too much, they will become dormant for an unusual amount of time; not blooming and slower growing for several years.  That is why I stress to hobbyists to find out how large the plant will get and then placing that plant into a pot or basket to accommodate the plant as a mature adult.  Keep in mind that the medium must be thoroughly thought about also.  Do not use a mixture of materials that will decompose.  It will cause problems with mold, mildew and funguses that may kill the plant faster than you can treat it.
           
            [The plant in this post belongs to Patt Lindsey; a hobbyist here in South Florida.  She supplied all of the photographs as well as doing the repotting.  Congrats to you Patt.  A job well done!]

Monday, October 8, 2012

Angraecum Crestwood

             Angraecum Crestwood is a multi crossed hybrid.  Starting with an Angcm. sesquipedale and crossing it with an Angcm. eburneum; coming up with Angraecum Veitchii.  Before I finish the hybridizing here, let me remind you that the Angcm. Veitchii had been posted earlier in this blog.  Take the Angcm. Veitchii and cross it with Angraecum sesquipedale again.  You end up with Angraecum Crestwood.

Angraecum Crestwood
 
             One of the odd traits of the Angcm. Veitchii was the fact that the flower always wants to open parallel to the ground.  In other words it wants to face down with the spur/nectary following suit, staying parallel.  That issue is actually called “twisty flower”.  The lip of the Angcm. sesquipedale is pointing down and slightly out while the lip of the Angcm. eburneum is upright appearing as a hood rather than a lip of the flower.  Angcm. Veitchii seems to open on its own terms.  Not following either of the parents traits.
             Cross the Angcm. Veitchii with Angcm. sesquipedale and it now opens with the traits of Angcm. sesquipedale.  The lip is now down and slightly out in the new hybrid Angcm. Crestwood.  It  looks very near an Angcm. sesquipedale; not as large but with the colors nearer the Angcm Veitchii, A white lip, with a slight green throat and white stripe down the center.  While the sepals and petals are slightly green in cast.  The two petals of the Angcm. Crestwood do not retract as much as they do in Angcm. sesquipedale.  The plant has bloomed in late spring through late summer; even into early fall.  The flowers will last up to four weeks if not in severe weather conditions.

Angraecum Crestwood
 
             Regarding culture; Angcm. Crestwood’s family tree contains two of the largest Angraecum plants that exist.  Keeping this in mind, it is best to pot/basket the Angcm. Crestwood in something large enough so that re-potting won’t be necessary every couple of years.  It will not get near as tall as it's lineage does; however it will not be setting on your window sill either.  It can reach in excess of 24 - 30 inches (75 - 90cm) and after five years or so have numerous kekeis or secondary plants from the main.
            Use a large medium of charcoal, aliflore, perlite and some lava rock.  The larger medium will give the plant ample space to grow its roots, plenty of drainage and air to let the root system breath.  In warmer months, water the plant every 2 – 3 days, trying not to get water on the leaves where it could sit in the leaves against the stem eventually causing stem rot.  Once cooler weather arrives, watering can be cut back to every 3 - 4 days.  If you notice any of the exposed root system starting to wrinkle, increase your watering habits.  I fertilize the plants every week year round (because of my sub-tropical climate here in South Florida) with a balanced 20-20-20 fertilizer.
             As the plant gains height, aerial roots will start to appear at the base of the plant.  The taller the plant grows more roots can eventually grow.  Do not damage these roots.  As with so many Angraecums, mess with the roots and the plant will go dormant and not flower for several years.
             When using a systemic  fungicide, it is best to spray the entire plant; especially the base or bottom of the leaves.  Make sure to allow the fungicide to reach the root system within  the pot/basket also.  If issues regarding fungus does appear, use a topical fungicide as needed until it is time to use the systemic mixture.
             Angraecum Crestwood does very well with bright, indirect sunlight.  My plants get a fair amount of 50% spackled light a couple hours a day.  The 20 inch (50cm) or so length leaves are broad and can be burned by direct sunlight.
             Angcm. Crestwood can be grown indoors in a large pot sitting on a table near bright light.  Do try and place the plant outdoors during warm weather.  It will appreciate the breeze.  Once temps reach an average night range of 55 degrees or below, it is time to move the plant into warmer surroundings.