This is just a short attempt to give the basic requirements for growing
tropical and sub-tropical, epiphytic orchid plants in temperate areas.
Please be aware that orchids are a huge and very diverse family of plants
and each individual species should be studied to understand it’s special
requirements.
How Do I Grow Orchids?
Growing orchids is like growing any other plant in that it comprises of
making a series of judgements rather than following a pre-defined set of
rules and instructions.
We need to learn the rules of watering, feeding, re-potting,
temperature-control and light availability.
We then have to assess our plants and the environment around them,
making a series of decisions as what or what not to do.
Be patient, don’t feel that you must always be doing something, it may be
that the best course of action is to do nothing and just look at and enjoy
our plants.
Remember there is always the option of thinking about it again tomorrow.
Essential elements
Let’s now look at the various elements that we need to understand. It is
important to understand that the balancing of these elements is just as
essential as the supply of them. One thing often affects another.
Watering and Water Quality
The first thing most people think of in relation to looking after a plant is
how to water it. To determine this we have to think about the plant’s needs
rather than what is convenient to ourselves.
We must never fall into the habit of thinking that the needs of our
plants are constant as they vary tremendously depending on several variables
like temperature, humidity and speed of growth.
The last thing they need is to be treated to a programme of
watering.
For example: - Once a week, Twice a week etc. A plant is a living thing
and like all living things it’s needs vary as it’s environment changes.
Remember that most of the orchids we grow have evolved to soak up water when
it is available and then survive until the next rains come.
Watch and wait until the growing medium (compost) is completely dry.
At this stage water your plant generously by giving it a good soaking.
Don’t worry about where you apply the water, plants can’t tell whether it
comes from the top, bottom or sides, the only thing that concerns them is
whether water is available or not.
An important point here is that you should use a method of watering that is
convenient. You can try dunking, filling the pot with a jug, putting it
under a running tap or any other method you please.
Just be sure it is thoroughly wet before you finish.
Once your plant is wet, drain away any excess water and then leave
it alone until it is dry again.
Don’t worry, strong healthy plants will wait for several days in a dry
state with no ill effect.
Therefore you needn’t be afraid that your favourite plant is going to
drop dead the minute it is dry.
The length of time between wettings will vary depending on things like
temperature, time of year, humidity, availability of light and state of
growth.
Is the plant growing vigorously or not?
Small, young plants have less of a reserve than bigger, older plants.
The volume of compost available in relation to the plant size also makes
a big difference to the rate at which the plants dry out.
It is worth remembering at this point that every time the compost dries
out we kill many of the rot-causing fungus spores that may infect our
plants.
Tap water seems ok in most instances.
My customers seem to be fairly evenly divided between hard water
users and soft water users, both seem to grow perfectly good orchids even
those in hard water areas.
One practice that is well worth maintaining is to keep flushing your pots
through with water whenever you water your plants.
By using copious amounts of water and allowing it to run through the pot
any impurities are diluted automatically each time you water.
Caution should be observed when using the contents of rainwater
butts as they can pick up contamination from several sources.
Most orchids are not particularly susceptible to cold water shock but it may
be good insurance to take the chill off very cold water before using it.
This may be as simple as taking some of the water from the warm tap
if that from the cold tap is liable to cause problems.
Heating Ventilation And Temperature
If we are growing orchids in the home, temperature control becomes academic
because we cannot let our plants dictate the temperature levels at which we
live our lives.
It is therefore a great advantage if we take the trouble to learn a
little about our plants needs before we buy.
Enquire of the vendors as to what sort of conditions his plants are
going to need and if they can’t answer satisfactorily it may be worth buying
from another source.
It is imperative when buying a plant to choose a variety that will suit
the environment it will have to grow in.
With this in mind we can go forward, remembering that orchids can be
adaptable and will usually tolerate short periods of time when temperatures
are not exactly to their liking.
If the published information advises a certain range of temperatures for
an individual species of orchid we can be fairly sure that a few degrees
above or below these levels will not cause problems.
Growing in a greenhouse or special structure is very different to growing in
the home environment, as here we need to learn how to control the
environment.
A heater with a thermostat and a maximum-minimum thermometer are
essential pieces of equipment.
Light
Light is the energy source for plants helping them to build substance and
strength.
Too much light is rare unless it is too bright in which case it can cause
scorching and burning. Not enough light results in soft, weak, pale-coloured
growth that is prone to pests and diseases.
Two things affect the amount of light available to the plants.
Light intensity or brightness and day length.
Day length is perhaps the most important as it is the main factor
affecting the amount of light our plants receive.
It can also influence the growth and flowering patterns. (Sometimes
plants tell what time of year it is by the length of the daylight hours)
In the home we are virtually stuck with the conditions that prevail.
However if we consider that light is always going to be in short supply
during the short, dull days of winter we should try to give our plants as
much light as possible.
Moving plants closer to south-facing windows is perhaps the best option,
if it is possible.
Certainly most orchids need to be fairly close to a window during the
winter to give of their best.
Weak sunshine at this time of year is actually beneficial.
This does not mean however that they are going to die if they get a
little deprived of light.
Often the only damage we notice is a reluctance to flower or we may
get a little bud drop on plants that have already started to flower.
During the summer months our plants can live further away from windows and
sources of light as there is no shortage at this time of year.
The real danger in summer is sun-scorch caused by the hot rays of the sun
burning leaf tissue.
For this reason we must keep our plants away from direct, hot sunshine.
In the plant-house things are different in that we have more light available
to start with because it is able to get to our plants from above as well as
the side.
This means that there are not many days in the year when light intensity
is too low for most orchids.
The big problem here is the probability of the light being too strong in
summer, causing leaf scorch and raising the temperature to unacceptable
levels.
The best way to counteract this is by applying some form of shading and
giving maximum ventilation during the brighter, warmer summer months.
The period between April and the end of September is the time that the
danger of scorch is highest. (This period may vary depending on what
latitude you are growing at)
Several different methods of shading and ventilation are available
and it is up to the individual, which they choose to use.
Feeding
Feeding need not be complicated and can be dealt with simply by buying a
purpose made, specialist orchid fertiliser and then following the
instructions.
Despite the many pages written and the hours of discussion by
various authorities I would heartily recommend the following course of
action as the simplest and best method....
The rules of normal good feeding apply as follows.....
Little and Often
It is better for the plants if they have a constant supply of nutrients.
For this reason it is beneficial to use feeds at a low concentration
regularly rather than a feast and famine situation of occasional, stronger
feeds.
However we must balance this with convenience.
It is also necessary to find a practice to suit ourselves.
Putting feed in the water every second or third watering is perhaps
a good compromise.
Do Not Over Feed
Stick to the manufacturers instruction.
A little extra for luck is not a good idea and can result in bad luck for
our plants.
Beware of Dry Roots.
If your plants are dry either water them well before feeding them or use a
weaker solution.
Strong feeds on dry roots can damage them.
Beware of Salt Build-up
Feeds contain a lot of mineral salts. Unless these are regularly flushed out
with water they may build up and damage root systems. See watering.
Trust The Experts
It is better to do the majority of feeding with a good quality, well
balanced feed that is targeted at orchids rather than to try finding the
correct balance and mixtures for ourselves.
Fertiliser firms all over the world are constantly researching to
find the best balance of materials to give maximum growth and productivity.
Lime/Calcium (pH)
Much is talked about this subject in relation to hard water and pH.
(Acidity/alkalinity) After many years of reading and listening to, so called
informed sources the only thing that I have concluded is that not enough is
understood about this subject.
I have even come across one book that calls for the use of soft water
because orchids don’t like hard water (water containing lime) and in a later
chapter recommends including lime when mixing composts.
Here are a few facts that I know to be true.
All plants need some Calcium. Even the ericaceous plants such as Azaleas
and Rhododendrons need some calcium and orchids are no exception.
Different species have different requirements, some orchids are known to
grow on limestone cliffs and rocks that are alkaline.
Others grow in moss and decaying plant detritus, which tends to be acid.
The majority of orchids probably grow in neutral or near neutral
conditions
Proof in the pudding I have been growing orchids in an area with hard water
for many years without being aware of any problems that were caused by the
high lime content of the water.
In conclusion, there are many types of orchid all having their own
individual requirements.
I think it is fair to say that the more commonly grown, houseplant type
orchids, can safely be grown in a normal, neutral or near neutral pH. In
cases where soft water is being used then it may be necessary to raise the
pH a little (make it more alkaline) by the addition of ground limestone or
chalk.
Humidity
Not all species of orchid need steamy wet jungle conditions, as is proved by
the millions of Phalaenopsis and other orchid species growing in our
centrally heated homes.
It seems that many orchids are able to cope with quite low levels of
humidity.
Certainly healthy plants with healthy roots can obtain all the moisture
they need through their root systems.
On the other hand a little damping down or spraying of water around
the plant-house when temperatures are high and background humidity low can
help our plants.
There are however dangers in providing too much humidity as this in itself
can encourage fungus diseases like Botrytis (Grey Mould), Leaf Spots and
Stem Rots all of which thrive in conditions of high humidity.
This is especially true in winter when our plants are already under
stress due to poor light levels and low temperatures.
The rule of safety for humidity is - `If in doubt do nothing’. Plants rarely
die for want of moisture in the air but can die or be severely damaged by
the diseases that are encouraged by atmospheric moisture.
A good damping down when the temperatures are high and everything will
dry quickly can help with growth rates.
Later, as your experience builds you may feel able to increase humidity a
little.
Resting
Sooner or later the budding orchid enthusiast will meet the term ‘resting or
rest’.
This refers to a period in some plants growing cycle when it stops all
active growth and goes dormant.
At this time the plant stops all visible activity and will sometimes lose
some or all of its leaves.
This state would normally coincide with the dry season in the native
country of that particular species.
In more temperate climates we can duplicate that dry season by withholding
water and possibly reducing temperatures as well.
Some thought should be given to this practice as although it may be
possible to rest plants within the confines of a plant-house it is not so
easy in the home.
Where ever you grow your plants, due regard should be given to your
plants needs rather than following books and rigid instructions.
A rule of thumb is that if a plant is in active growth it will probably need
watering.
If it is not showing any signs of active growth, don’t be in a hurry to
water even if it seems a little dry.
If it is growing in low humidity (In the home) it will need some water to
stop shrivelling.
Most houseplant orchids don’t need appreciable rest periods.
To Sum Up
Most plants have to be very adaptable in the wild due to the wide range of
conditions that they have to endure.
We grow orchids for pleasure and so it is important that we enjoy them.
To this end let’s all relax, sit back and first and foremost enjoy our
plants and not let them become a source of worry.
Make your own decisions so that you get from your plants what you
want.
