Your Basic Orchid Course: Learn All
About Orchids

From: Melissa Moravec &

This is your basic orchid course and is meant to give you an overall guide to the wonderful world of "orchids". This should be esspecially helpful if you are new to growing orchids. This will be separated into sections including some history, the nomenclature, what to look for when you are buying your orchid plants. This basic orchid course will also provide you with some orchid care tips.


Orchids have been around since almost the beginning of time. They were around when the Greek  had their empire.  We have seen the orchids used as a sign for love, for virility and  luxury over the centuries. They have been also used as an aphrodisiac.  It wasn't until the 18th century when cultivation seemed to take a turn for the better.

The world over you will see evidence of orchids. They grow and can be found anywhere in the world. Although a great deal come from warm, and humid climates like Southeast Asia and South America they can also be found throughout the US including Alaska. If we look at the extremes that some orchids go through in some of the areas of the world I can understand that they are indeed hardy plants and can withstand some of the torture that we put them through in our homes.

Gardening orchids was then becoming more than just a hobby of the rich.  Some of the botanists were actually trying to produce hybrids. William Cattley was an early botanist noted some orchids which were shipped in a container as packing material, so he re-potted the material. During November of that year he noted that they blossomed and determined that these could easily be reproduced.

The late nineteenth and twentieth century showed the real start of reproduction techniques. The flourishing of hybrids truly began and the many thousands of hybrids and varieties became reality. Today, there are well over 10,000 varieties and over 110,000 hybrids.

Orchid Naming

There are 4 main types of orchids that we see today, they are organized by their growth habitat. The majority are epiphytes or air plants. These plants use tree bark as their growing base and feed off the nutrients on the trees and from the rainfall. Lithophytes are also air plants but they grow on rocks. Saprophytes grow on dead vegetation and are also air plants. Terrestrial orchids are the only exceptions to the rule, these orchids actually are ground plants and grow in soil.

We have to thank the early botanists who determined the nomenclature or naming of orchids. This standard is known world wide no matter where you are from. Orchids are probably the only plant that has this world wide acceptance of naming. The taxonomists are the people who do most of the naming. The actual pronunciations of the Latin names of the genus is a different matter. There have been heated debates on the actual pronunciation.

Naming is divided into various categories; first there is the name given those plants with similar plant structure characteristics. This is the "genus" and usually within the genus there are at least several species or hybrids. Species indicates that this subgroup of orchids share one or more characteristics which sets them apart within the genus. Hybrid are the result of propagation between different genus or different species. Next in order you will see what is termed the "cultivar" This is what distinguishes hybrids or species apart from one another.

Now when you look at orchid plant names the genus is always the first and is capitalized. So names like Cattleya or Phalaenopsis are genera (pleural of genus). Next would come the species these are always written in both small letters AND italized. Hybrids are always in small letters and not italized. The cultivar is next and it is distinguished as the third name AND is surrounded in single quotation marks. Occasionally you will see the cutivar noted with a single quotation mark and an X between two names. This means that the hybrid is the result of the two genus and species and it is not registered in the nomenclature yet.

Here are a few examples of the all of this put together; Cattleya Hyrida: A cross of the first Cattleya orchid hybrid that was created back in 1863, made from two Cattleya species: C. loddigesii x C. guttata. Cattleya is the genus and Hyrida is the hybrid, whilst loddigesii is the species.

Slc Jewel Box 'Scheherazade' (Ansac x Cattleya aurantiaca):The genera are a combination of Sophronitis, Laelia and Cattleya, the hybrid is the Jewel Box and it is not registered because it states how it was propagated.

Light: is a very important part of the needs of orchids. As air plants they grow in different light. As noted above some of the plants grow low in the forests and get some diffused lights while others grow higher on trees and get bright light.  The same goes when they are grown either in outdoor gardens or as house plants.


Light needed

Growing Area

Cattleya, Brassovola, Epidendrum

Laelia, Sophronitis

Medium to high

Outdoors, Sunny window

Fluorescent lights


Medium to high

Outdoors, Sunny window


Medium to high

Outdoors, Sunny window



Outdoors, Moderate sunny window

Fluorescent lights



Outdoors, Moderate sunny window

Fluorescent lights


Medium to high

Outdoors, Sunny window

Fluorescent lights


Low to medium

Fluorescent lights, window with shade

Outdoors with shade


Medium to high

Outdoors, Indoors bright indirect light


Medium to high

Outdoors, Very sunny window

Low intensity means the light is filter and for about 3-4 hours per day.  It does not need to be in the direct sunlight.

Medium intensity means that the orchid plant can be in direct sunlight for about 4 hours a day

High intensity mean that there can be direct sunlight for up to 6 hours per day.

Light is the friend of orchid plants. If in doubt light should not be lessened. In fact, you can increase the light to orchid plants and many times this will clear up some of the problems you may be having with the plants.

When you are looking into buying an orchid plant you need to consider where you will put the plant. This will lead to buying the right plant.


There is no real art to watering orchid plants.  Some orchid plants will hold water in what are known as pseudopods. These are pockets within the roots where water is absorbed into and provides a reservoir for the plant. Generally, watering should occur several times a weeks.

Watering will vary depending on the temperature the plant has been exposed to, the humidity and the sunlight are the main ones you need to be concerned about. Other factors include air movement, potting material and size of the pot.

Understanding that water is absorbed by the root system allows us to check if water is needed. The easiest way is to put the small finger into the potting material about 1 - 2 inches down. The top of the potting material will almost always be dry but under the surface is where the need can be determined.

Another method is to use the pointed end of a pencil. Push it down about 1- 2 inches and let it stand their for about about 30 seconds and then pull it out. If the end is damp or shows evidence of water the plant does not need to be watered.

When watering takes place do not use cold water, use lukewarm water. Also, be sure that all parts of the plant in the pot are watered. Make sure that there is enough water so the water comes out the bottom of the container.

For other evidence for watering or not look at the leaves. If they are thin this is usually a sign that more frequent watering is needed vs. when the leaves are thick. Also, if the pot is large and made of plastic, there should be more frequent watering.  Clay pots do not need frequent watering generally because they are porous.

Humidity is important for most orchid plants. Orchids love the humidity to be about 40-70% . Most plants get enough humidity in a home but some species like it better either in high humidity area of the home like the bathroom. But there is another very easy way to cure this problem. Use a humidity tray. This is plastic or metal tray filled with pebbles. Then put in some water to about 1/2 to 3/4 of the tray. You do not want the plant to sit in the water as this will cause it to wither.

Another way to enhance humidity is to use a fine water spray or mist. You will need to experiment to find out how often to mist. Generally this would usually come out to once a day or every other day. Use this if your home is very dry.

Fertilizer is used and is also a must for orchid plants.  There are a great many fertilizers on the market. It is very important that you use one that is specifically is for orchids. about once per week during growing and blooming. The fertilizer is used in a very dilute mixture. It is diluted with usually 1/4 to 1/2 teaspoon of mixture with a gallon of water.

There are different orchid fertilizer mixtures which differ usually by the percentage of nitrogen in the mix. The nitrogen percentage is noted in the first  of the three numbers on the mixture. Usually a balanced mixture is best. Using other mixtures woudl be necessary only when you become more conversant during the growth periods of the plant.

I find that the best way to add fertilizer is to use the same technique as watering the plant. Remember, you put the plant in the sink so you can water for about 1 minute and let the excess water escape down the drain. You can use the same technique with adding fertilizer. Before you use the fertilizer mixture water the plant first then use the fertilizer. As I mentioned earlier in the growth and blooming season fertilize weekly and in the dormant state fertilize every other week.

Growing Medium

There are many different types of growing media that can be used with orchid plants. The basics, though, need to be followed. For a lower temperature environment like the northeast or northwest U.S. where the temperature outside varies from 45-65 degrees and the humidity is moderate, the mixture of fir bark and sponge rock is very appropriate. You can also augment with the addition of a coarse stone. This mixture does well in these climates.

In dry climates with a low or medium temp environment, the use of moss or seaweed is a good addition. Now this does not mean that the medium is used for decoration. The medium is used as an ingredient for the mixture. The caution here is that moss or seaweed can also harm the plant by holding too much moisture and cause root rot. Moss and seaweed have the highest moisture retention. Be sure that the climate is dry before using this for more than decoration.

What about in warmer and dry climates? You will need more retention of moisture. So you would need a medium with tree fern, fir bark and /or charcoal. No, I don't mean the charcoal we use for the bar-b-que. These substances will hold the water moderately. So when the climate is warm and  humid,  stone and sponge bark would be my choice for a growing medium.  The stone should be a mixture of coarse and fine stones.

Orchid Diseases: The Flower

The orchid flower is usually a thing of beauty. When diseases strike it can be tell - tale. Like the leaves, the flower can tell you a great deal. Let's take a look at what we will learn.

Spotting of Flowers

A sign of fungal infection or mold is pink or light brown spots on the flower. When you see either, orchid care will suggest to be careful with your other plants as the infection can spread to other plants.

Remove the orchid flowers that are affected. The remedy is to get more circulation.

Flowers With Punctures

Yes, those aphids can get at orchids, too. Also, some insects including Thrips.

Orchid care the flower suggests that the remedy is spray the orchid with malathion, but be careful and use a face mask.

Flowers With Mottled Colors

Here caring for orchids will strongly suggest a second opinion is necessary. The cause could be a color losing virus. Even if this is suspected then isolate the plant. If it is a virus then you need to destroy the plant.

Bruised Flowers

The causes of bruising are many.  It could simply be from mechanical injury. If this is the case the area of damage will not increase or go on to other flowers.

But it could also be from slugs or even cockroaches. You may need to investigate and use some dust to bait them. If from cockroaches then diazinon or Sevin on the ground around the plant, on the plant and the pot as well.

Caring for orchids also shows that the bruising can be from red aphids. If so use the malathion treatment.

Rapid Wilting Of The Flower

If you see wilting of the flower, especially the dorsal or upper septal this can be caused by a sudden temperature change or pollination from an "unknown" pollinator. (I didn't think orchid flowers were that particular!!)

The remedies are those that make sense, moderate the temp changes and remove the affected flowers. Not sure what to do for the unknown attacker.

Deformed Flowers

Caring for orchids is not complete without the a word about deformed orchids. Common causes include;

  • low humidity or high temp when the buds were developing
  • mechanical or chemical injury during bud formation
  • the bud has acquired an unexplained deformity
  • the potential of a virus infection, (you see many of the flowers have the deformity). Need to isolate the plant.

Caring for orchids does involve looking at the "whole plant". In orchid care the flower is important.

Orchid Diseases: The Leaves

Over the past 20 years the orchid supply has become almost limitless. Learning about leaf orchid care is becoming more important to all the orchid lovers.

Leaves can help you to diagnose what is wrong with your plant. I imagine this as one of the best ways to see the early signs of potentially fatal diseases.

Leaves can be yellow, blackened or brown or they may become shriveled. Let's learn more about leaf orchid care and what to do.

Blackened leaves show their effects on the body or the tip of the leaf. If it is on the body of the plant it is usually due to the hot sun causing a leave to burn. Leaf orchid care would tell us that if this may to the case put the plant away from direct sunlight.

orchid bacterial

If sun burn is not the cause and the size of the spots continue to grow then it may be a bacterial or fungal disease. If so cut off the affected part of the leave and treat it will a fungicide like natriphene. It also could be caused by excessive fertilizing, especially cymbidiums or once again a fungal infection. If it seems to become larger you need to cut off the affected and treat the plant with a fungicide.


Leaves may also be mottled or streaked black or brown. They are telling us that this could be from a viral infection. Caring for orchids tells us to determine this special tests are needed and can be provided b your local agriculture experiment station. You will need to send in a leave. As in humans, there is really not much for treating this right now.

Yellow leaves are probably the most common ailment we see. Good leaf orchid care would tell us that it just could be a natural phenomenon called old age. If it seems to e happening to the oldest leaves don't worry.

On the other hand it could be from, too much light (most common), not enough nitrogen in the fertilizer or if the medium is primarily bark. Other causes include being subjected to low temps or loss of roots.

Caring for orchids would suggest to first change the lighting and potential for low temps. Keep in mind that in the North being on a window sill during winter can be a cold spot.

Another condition that you could see in orchids are small spots that turn from reddish brown to black. These are most likely caused by fungal infection.

As orchid growers we need to remember that humidity is needed for proper orchid growth and the orchid supply. Too much humidity favors the growth of fungus.

The last orchid care tip I want to mention is the shriveling of the pseudobulbs. Pseudobulbs are very efficient water storage areas of the plants. If there is not enough water given to the plants or the humidity is too low the leaves will shrivel. Also, if the root system is dying you can get shriveled pseudobulbs.

Leaves tell us a great deal and the leaf orchid care helps to prevent the early diseases from becoming fatal to the plant.

Orchid Diseases: The Roots

The final part of your basic orchid course in orchid care is about the roots of the plant. This is the heart and soul of the plant. If these are not healthy then the whole plant will show the effects.

Loss Of Roots

Orchid care now turns our attention to the roots. Roots disease is difficult to diagnose. The roots actually lose their function and do not supply the plant with the nutrients it needs.

Some of the causes include:

  • over watering, probably the most common. I know I am at fault for this one with one of my phals.

  • the next most common cause is old potting material. You will see this occur with orchids bought from grocery stores or home goods stores. They are usually packed in soil which is not a good medium for orchids.

  • slugs or snails can cause root disease. This orchid care says you need to treat with metaldehyde.

  • sometime excessive salt or minerals in your water can cause this as well. If so you need to use distilled water.

Occasionally you will see the whole plant be effected by the infamous "mealy bug".

When this occurs you will note a white cottony mass on the plant or a gray, brown or even black mass underneath the leaves and flower stems.

The treatment includes scrubbing the plant with a soft toothbrush dipped in malathion. You should also spray the greenhouse regularly with malathion. Don't forget to take precautions with spraying, no children or animals and use a face mask.

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