Showing posts with label Philippines 2010. Show all posts
Showing posts with label Philippines 2010. Show all posts

Sunday, December 5, 2010

Understanding the Epiphytic Orchid

Orchids I saw at the gardens of the  Intercontinental Hotel (Makati).

The Mediterranean climate here in California allows us to grow a wide variety of exotic plants.  However, with my recent trip to the Philippines, envy crept all over me and my humanity gave in when I saw the way orchids are growing there.  I can grow them here but it would not be as easy as when they are grown in their native habitat.   Here we enjoy the dryness of the Mediterranean air and despise the humidity of the tropical breeze.  However, we know that the epiphytic-orchids feel the other way around.
 
The Greenbelt Shopping Center boasts beautiful orchids that are planted between buildings.

Epiphytes.  Epiphytic plants (roots are above ground) like most orchids derive nutrients and water from the atmospheric air.   Orchids growing on tree trunks are a common sight in wooded areas of the Philippines as well as in home gardens and as well as in public gardens.  Gardeners bring these beautiful plants near their homes and they tie them to a tree and voila!  Unlike their terrestrial counter parts that have a prolonged access to soil moisture, epiphytes live in a more or less arid (zerophytic) conditions.  The roots, being in the air, are dry most of the time.  Water from the rain settles down way below the reach of the roots.  Sunshine not only provides the needed light and warmth to the leaves but it also lifts up the water up in the form of vapor.   Here in California, the air is so dry that it sucks even the moisture from my skin.   Before the orchid has a chance to drink a little, the moisture vanishes in mid air.
 
                       
Orchids growing on trees near my sister's house in Cagayan.

Adaptation mechanism.  Orchids generally require 60-80 percent relative humidity for optimum flowering.  This high humidity requirement is not always achievable but orchids have adapted to the fluctuating available moisture.  Leaves come in different shapes (flat, folded, or even pencil-like leaves) and all these help the orchids adapt to their environment.  Most orchids have thick fleshy leaves, similar to that of the succulents that allow them to store water and resist drying out.

                       
More orchids at Greenbelt, Makati. 
The gardens provide a pleasant place to take a break from stressful Christmas shopping.

Orchids have specialized roots called velamen.  These are the white shimmery roots (as seen in the above picture).  These are the roots that are used to both anchor the plants and absorb water and nutrients from the air.  What is special about the velamen is that they are made of multi-layered thick cell walls.   The property of the velamen prevents cellular collapse during periods of dryness and acts as a barrier to water loss.  When the tips of the velamen are green it means that the orchid is happy. 

Orchids at my old High School (ANRVHS) in Abulug.

In the Philippines, just like any other marine tropical place, orchids grow voluntarily on trees.  The home-grown orchids likewise, perform naturally well.  On the contrary, growing epiphytic orchids here is like having a plant in ICU all the time.  


Many times I have tried growing epiphytic orchids here in my garden; so far I have not had much success.  Is it just me or is it the climate? 
Related Posts with Thumbnails