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Extension Folder No: E-117/ Ranchi-40
An Overview
ICAR Research Complex For Eastern Region
Research Centre, Ranchi
Plandu-834010, Jharkhand
Growing OrchidGrowing Orchid
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Orchids are native to tropical regions but with little efforts and care, they can be grown anywhere
in the world. Orchids are among those owers which come in a variety of colors. Orchids grow in the
most diverse climatic zones. Some ourish in continually moist, warm regions, others in regions that
are warm and moist some of the time, others again in regions that are dry and hot in the day time and
moist and cool at night. Regular airing or ventilation is extremely important for the growth of orchids
in particular for their aerial roots. Water should always be at room temperature, slightly acid and soft.
Orchids prefer weak acid water with a pH value of around 5 or 6. Under natural habitat, orchid receives
nutrition from the breakdown of dead plants and is supplied in rainwater that drips from leaf to leaf and
nally to the orchid.
Orchids have different life cycles to most other indoor plants. They do not grow in garden soil or
ordinary houseplant compost, but in special orchid growing media and require relatively few nutrients.
Proper management of ve elements of temperature, light, air, humidity and nutrients is essential for
production of enchanting owers.
The life of orchids is characterized by an alternating cycle of growth periods and rest periods.
The rest phase corresponds to the winter period. Many orchids ower shortly after the rest phase. If
the orchids are exposed to too much moisture during this phase, they will not ower and will form only
weak new shoots. There are two types of growth patterns for orchids, sympodial and monopodial.
The monopodial orchids, Phalaenopsis and Vanda being the two most common, grow up off a single
central stem with leaves on either side. Sympodial orchids have multiple growths and usually grow
one or more new growths per year.
Often the growth pattern looks
like a corkscrew with each new
growth coming from the side of the
one before it in a circular pattern.
A polyhouse can proved to be
a good and ideal place to grow
many plants including orchids.
Light, temperature and humidity
are some of the conditions which
can be maintained very easily in a
polyhouse.
Temperature
In the natural habitat, orchids like lot of warmth, night time temperatures are often around
7-12o C lower than the day time values. This night time temperature drop is necessary for the formation
of owers in many orchids and should be at least 4-6oC.
Polyhouse for growing orchid Shadenet house for growing
orchid
IntroductionIntroduction
Growth CycleGrowth Cycle
Important tips:
Terrestrial orchids without bulbs and with relatively soft leaves do not need direct
sunlight. E.g. Paphiopedilum.
Epiphytes with large, eshy and no bulbs will not cope well with a lot of sunlight. E.g.
Phalaenopsis.
Orchids with relatively tough leaves with large surfaces and relatively well developed
bulbs will not require direct sunlight until they reach the owering stage and begin to
open. E.g. Cattleya, Cymbidium, Laelia, Odontoglossum, Oncidium.
Orchids with narrow, tough, leathery leaves and large bulbs are genuine sun lovers.
E.g. Vanda.
Orchids with narrow leaves, almost like stems or with striated leaves and with no bulbs
are well adapted to great intensity of light. E.g. Dendrobium striolatum.
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Humidity
Humidity levels of 60-70% are the ideal conditions for the growth of orchid. Humidity levels can be
raised by misters, electrical humidiers, plastic grid or a specially equipped plant container.
Mister: These misters supply the sufcient humidity to the plant. It is better to spray the leaves in
mornings, so that the plant will have plenty of time during the day to dry off before the temperature drops
at night. It is not advisable to spray any plants while the sun is shining on them. The minute droplets of
water will act like magnifying glasses in sunlight, and may cause burns on the leaves.
Tips for increasing humidity
A bowl full of water should be placed between the orchid pots.
Use waterfalls, indoor fountains, a spring stone surrounded with plants or aquariums.
Light
Orchid needs an abundance of light, and can withstand direct sun on their leaves early in the morning
or late in the afternoon / evening. The light intensity required for better growth and owering is 25 to 30
Kilo lux. They require shading between 11am to 3pm where the light intensity is too high. Generally, during
bright sunny days, 50% shadenet, while during cloudy days 25% shadenet is used.
Ventilations
Regular airing or ventilation is extremely important for the growth of orchids in particular for their
aerial roots. Fresh air will prevent decay and the proliferation of fungi and pests.
The growing media of orchids varies according to the habitat. The growing media for epiphytic orchids
contains tree bark, terrestrial orchids require soil medium and lithophytic orchids grows in rocks. The
different components of growing media are,
i) Tree bark: Shredded Katus bark from Castanopsis hysterix is widely used.
ii) Coconut husk chips (CHC), made from the pithy covering outside of the spherical, hard coconut
shell,
iii) Cocopeat: “Coco-Peat,” is the result of grinding the husk into coarse powder.
iv) Perlite: Perlite, often referred to as “sponge rock”, is expanded volcanic glass, and is a great
aerator and holds enough moisture.
v) Pumice: It is similar in nature to perlite, but with a higher density and lower moisture-holding
capacity.
vi) Leaf mould: Dried and partially decomposed leaf. A good choice for terrestrial orchids, releases
lot of nutrients as it decomposes, high in water retention capacity.
vii) Brick pieces: Small pieces of brick added to the media for increasing porosity of the medium.
They are high in thermal mass,
it is good to have them in a
combination for hotter and drier
climates.
viii) Vermiculite: It is having high
water holding capacity. It
gradually releases nutrients
for plant absorption. On an
average it contains 5-8 %
available K and 9-12 % Mg. It
can x ammonium into a form
that is not readily available to
the plant. This xed nitrogen is
gradually transformed to nitrate
by microorganisms making it
available for plant uptake.
Growing MediumGrowing Medium
Properties of some most commonly used growing
media
Media Moisture
Retention
Thermal
Mass
Watering
Frequency
Stability
Stone/bricks Low High Frequent High
Perlite High Low Low High
Leaf mould Medium Low Medium Low
Cocopeat High Low Low Medium
Coconut husk Medium Low Medium Medium
Sponge Rock Low Low Frequent High
Tree Fern Medium Low Medium Medium
Katus Bark Medium Low Medium Low
Charcoal Medium Low Medium Medium
Moss High Low Medium Low
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ix) Sphagnum moss: It is very good for encouraging
new growth; therefore a good choice for seedling
orchids.
Leaf mould
Leaf mould + Coconut husk
Leaf mould + Coconut husk
+ Brick piece
the leaves become limp, drop off or turn yellow; the roots decays and growth ceases. In too little
water, the pseudobulb shrivels, the roots turn brown and wither, and the leaves go limp, drop off or
turn yellow.
For young plants the amount of nitrogen is increased e.g. NPK at the ratio of 30:10:10 (0.1-
0.2%). Too much nitrogen may produce soft, unhealthy plants.
For intermediate growth stage, a balanced fertilizer mixture may be given e.g. NPK ratio of
20:20:20 (0.1-0.2%).
For owering stage, adults plant may require an increase in potassium and phosphorus. e.g.
NPK ratio of 15:25:25 or 15: 30:30 (0.1-0.2%).
Fertilize twice a week during growth periods.
Fertilize once a month during rest periods (winter).
Never fertilize freshly repotted plants.
Based on structure of
roots of orchids, the media
may be prepared. For ne
rooted orchids a ne grade
media is desirable, whereas
orchids with thick and chunky
roots will do well in coarse
grade media.
Media preparation
(4:2:1 = Leaf mould: Coconut
husk : Brick piece)
Clay pots are air and water permeable and are more
stable because of their weight, but they dry out a lot faster
than plastic pots and may allow salts to accumulate which in
turn can burn the roots of orchids. Plastic pots do not allow the
growing media to dry out quickly and will always remain clean.
The best plastic pots have thick walls in light colours, which do
not break easily and will not heat up in strong sunlight.
Plant ContainersPlant Containers
Water should always be at room temperature, slightly acid
and soft. Orchids prefer weak acid water with a pH value of
around 5 or 6. Watering depends on many factors such as,
On the type of growing medium
On the plant container being used. Orchids in plastic pots
will not dry out as fast as those in clay pots.
On the humidity level, the higher the humidity the less
often need to water.
On the temperature
On air movement
On the growth of the plants. An orchid that is going through
a growth phase and is producing many new shoots will
require more water than a plant that has nished growing
and is conserving energy for the ripening of its bulbs and
for forming owers.
Watering and spraying should be done in the morning
hour. This will allow the plant enough time to dry off before
the slight drop in temperature towards evening. Orchids are
watered from above to moistened the growing medium and
to avoid the water to run over the plant itself. The orchid pots
should not be placed directly on the ground or on a table as the
air is necessary to circulate beneath the pot. In excess water,
WateringWatering
FertilizingFertilizing
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RepottingRepotting
Fertilize more often using a greatly diluted fertilizer.
Fertilize only when the plants are in growing and require
nutrients for their development.
Never pour fertilizer on to a dry growing medium.
Fertilize only well-rooted, healthy plants.
Repotting is necessary in the following circumstances
If the growing media has become hard and dense and is no
longer for air or water to be permeable.
If the plant is too large for the pot and is constantly in danger
of tipping over.
If a plants new growth is becoming too much for the old pot and is beginning to grow over the edge.
If the plant is sick.
When to repot
The frequency of repotting will depend on the shape and growth of the orchid and also on the type
of growing media. Plants may grow for years in completely synthetic polystyrene chips. Natural growing
media, which will decompose and break down over a period of time, will have to be renewed more
often. Sympodially growing orchids will have to be repotted approximately every 2-3 years on average,
for example Cattleya, Cymbidium, Dendrobium, Laelia, Odontoglossum, Oncidium. Monopodial orchids
are repotted every 3-4 years, for example Vanda. Paphiopedilum, and phalaenopsis should however be
repotted every 2-3 years. Always repotting is done at the beginning of a new growth period. That time will
be recognized by the appearance of fresh, light green shoots and when the orchids begin to form new roots.
How to repot
Water the plant well the day before repotting so that its roots are smooth and exible rather than dry
and brittle.
Carefully loosen the rootstock in the old pot.
Now shake the root stock gently without allowing plant to fall apart. Parts of the roots that look
diseased, dried up or shrunken should be cut off with a very sharp knife (disinfect knife with alcohol
before cutting). Plants that are too large or very old can be divided when repotting.
Place a thin layer of new growing media on top of the drainage layer in the prepared pot. Place the
root stock on top of this and surround it with rest of the media. While doing this, occasionally tap the
pot against the edge of the table to help the media particles to shake down into all the cracks and
spaces. Monopodial orchids should be placed in the centre of the pot. Sympodial orchids can be
placed in such a way that the oldest bulb is close to the edge of the pot while the new shoots are in
the centre.
Allow a space of 1-2 cm around the plant for watering purposes.
Potting and Repotting
Every orchid growing medium should
have the following characteristics:
It should be permeable to air and
water and retain warmth.
It should be light weight and loose
but still hold the plant securely.
It should absorb water easily but
also drain quickly.
It should show a slight acid pH
value.
Fungicide treatment Placing of brick at the
bottom of pot
Placing the plant in the
pot
Filling the pot with
growing media around
the plant
Steps in Repotting
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Aerides multiorum Coelogyne species Cymbidium ‘sleeping nymph’
Dendrobium densiorum Oncidium species (Dancing girl
orchid)
Paphiopedilum hirsutissimum (Lady’s
slipper orchid)
Phalaenopsis species Phalaenopsis manii
Vanda blue magic
Correct Citation: Naik, S. K., Maurya, S. and Choudhary, J. S. 2014. Growing orchid- An overview.
Extension Folder No: E-117/ Ranchi-40. ICAR Research Complex for Eastern Region, Research
Centre, Ranchi.
Authors: S. K. Naik, S. Maurya and J. S. Choudhary
Published By: Director, ICAR Research Complex for Eastern Region, Patna
For further information please contact: Head, ICAR Research Complex for Eastern
Region, Research Centre, Ranchi Plandu-834010, (Jharkhand) Phone: 0651-2260207,
Fax: 0651-2260141
Designed & Printed by : The Composers Press, New Delhi. (M) 9810771160, 011-25707869
Orchid SpeciesOrchid Species
After repotting
Place the freshly repotted plant in a bright, but on no account sunny position.
New root formation will be encouraged if a heating mat is placed underneath the pots.
Orchids should not be given water immediately after repotting. Because the damaged parts of roots
are better able to heal in growing media that is merely moist and fresh. The minimum moisture
encourages the roots to grow.
After 8-14 days, the plant may b e watered normally and according to its requirements.