Pleurothallis spp.
John Skillcorn
Costa Rica
Latest update: 17 August 2002
There
are many hundreds of species of Pleurothallis orchids, and they range in
size from the tiny yellow thing you see to the left of the page with flowers
only a few millimeters across, to very large
plants standing over a foot tall. They are very difficult to identify
because of their similarities while not in flower, and even when they are
flowering their flowers are often very similar, tiny and can be identified only
by a botanist. Nevertheless, they are attractive and reasonably tough
little plants and many should do well in vivaria suited to Dendrobatids.
This small plant
(Pleurothallis arietina) produces
flowers which, in many Pleurothallids, typically sit on top of the
leaves. The flower form here is similar to a bivalve mollusc.
They are all epiphytes and grow on twigs, tree trunks and branches,
often high up in the forest canopy and so are difficult to spot. On
the odd occasion Nature plays her part and breaks off a twig or branch,
letting it fall to the ground. It is now that we can gain access
to those very special plants that are otherwise out of reach. Better
still, because the plants would undoubtedly perish on the forest
floor we can feel safe in securing these for our own uses without
feeling guilty. |
|
Pleurothallis condylata
The pictures above show a
medium sized orchid which produces a never-ending supply
of substantial flowers. As one flower fades another takes its
place on the stem, a characteristic shared by many Pleurothallids.
Because
these are mainly small to very small plants, their flowers are correspondingly
tiny. Nevertheless, as you can see from these pictures they can still be
intriguingly beautiful.
Pleurothallis setosa
Looking more like a
small, furry animal than a flower, this orchid produces its flowers at
the end of long, rambling, very thin stems. A succession of
flowers is produced from the same stem, one after the other. The flowers can either
sit on the substrate or be free-hanging, as shown in the pictures below
and left respectively.
As has already been said, these orchids are epiphytes and as
such cannot stand having their roots permanently immersed in water. A
humid atmosphere will probably supply them with all the water they need.
However, a daily spray with rainwater would be beneficial providing they can
dry
off fairly quickly. A feed with very weak fertilizer (half strength or
less) once a week while they are actively growing should provide them with the
minerals they need. In nature, they would simply rely on any small
particles of debris becoming entrapped in the roots holding them to their perch
and are therefore not accustomed to large amounts of feed.
These final three
examples of this extremely diverse group of plants show yet again three
further forms. Upper right one sees a medium sized plant which
produces tiny, pink but fragrant flowers in abundance. Left is P.
strumosa, a small epiphyte with leaves only some ten or twelve millimeters
long. Finally, upper left, is P. tribuloides, a species which
produces scarlet flowers very close to the base of the plant.
Lighting should be bright, but full sun should be avoided at
all costs for most species. Remember they grow in dim conditions within
the forests, and even those high up in the canopy have the benefit of shade from
the tree's leaves. Good quality fluorescent lighting should provide them
with all the light they need to grow and flower. Keep an eye on their
progress and adjust their position and/or the lighting accordingly.
Temperature requirements vary a great deal, depending on which
part of the country the plants come from. Those from mountainous areas are
perhaps not the best species to attempt to grow in vivaria alongside Dendrobates
species. However, there are many species that originate from within the
tropical rainforests and these are the ones to try.
