Table of Contents
- 1 Types of Orchids
- 1.1 Botanical species can be bought from specialist orchid producers.
- 1.2 The substratum for orchids
Types of Orchids
Orchids grow throughout the world between the North and South Poles, excluding deserts, and between roughly 0 and 3,5000m in altitude. USA has the biggest number of different species in Europe. Depending on the source, there are 25,000 and 35,000 different species, divided into 800 types. They are epiphyte (growing on other plants), or lithophyte, (growing on rocks) in hot regions, or terrestrial in regions with a more moderate climate.
There are over 100,000 hybrid varieties, which are sold in most garden centers and which are very easy to grow. These are familiarly called “window sill orchids”. Reproduction by meristems, a sort of cloning, make these types of orchids easily available. They are also easy to grow indoors. It is, however, useful to know the name of the orchid, or at least its type, in order to adapt its growing conditions to the environment.
Peacock orchid and Bletilla striata orchid bulbs are more and more common in garden centers in spring. These are Asian terrestrial orchids.
Botanical species can be bought from specialist orchid producers.
Orchids like a high humidity level and the presence of other plants. They appreciate having their leaves bathed every day and a saucer of humid gravel or clay stones placed under their pot. They also like a gentle ventilation but detest cold air currents which cause their flower buds to fall (for example, the Phall). In winter they appreciate a maximum of light (put them on a window sill facing south, without shade). In March or April, they should be placed in slight shade facing north (depending on the species and the latitude).
Terrestrial orchids sleep during the winter in cold and moderate countries. Those which grow in hot, dry countries, like Australia, may sleep in summer.
The main types of orchids, created to be sold as cut flowers, are :
- Phall and related types
- Boat orchids
- Paphiopedilum (Paph)
- Oncidium (Onc.)
- Blue orchid and related types
- Odontoglossum (Odm.)
- Miltoniopsis (Mltnps)
- Epidendrum (Epi.)
The most common orchids growing in the wild are the Dendrobium and the Bulbophyllum (Bulb.), each consisting of between 1,000 and 1,500 species. Orchids have a diversified vegetal make-up :
1. Terrestrial orchids possess :
- either an underground tuber (Orchis, Dactylorhiza, Cypripedium).
- or apparent tubers called pseudobulbs (Himalayan Cymbidium).
- or roots at the base of the plant only (Paphiopedilum, exotic Cypripedium). This type of vegetation is called sympodial.
2. Epiphyte or lithophyte orchids possess :
- either pseudobulb in various shapes and aerial roots which cling onto the plant or rock in order to feed itself (sympodial orchids).
- or one leafy stem, which grows, and aerial roots (Vanda, Vanilla). These are monopodial orchids.
The substratum for orchids
The substratum for epiphyte orchids
The nature of this substratum isn’t very important as its purpose is to support a plant that lives on a tree. It should be as inert as possible, ventilated, and it should retain an amount of water suited to the growing conditions of the plant in its original environment (thus it is important to know the name of the plant).
You can use
- horticultural pine bark, which lasts around 3 years.
- well washed coconut fiber, which will get rid of sea salt (be careful of rot caused by over-watering).
- cork cut up into small pieces (wax-free wine corks).
- or a mixture of one of the above with polystyrene of different sizes, or with a small quantity of perlite or vermiculite (this helps roots to sprout).
Some epiphytes are sold in baskets. They may be reported to help them grow. Or you may simply place the basket in suitable pot three-quarters full of humidified clay stones.
We could all go out of our minds trying to find a personal mixture – but it is much simpler just to use horticultural pine bark (not that used for embankments) of different particle sizes, depending on the thickness of the roots. A small particle size is suited to thin roots, medium or big sizes to the others. Good stability and drainage can be obtained by putting 2cms. of clay stones or bits of broken pots at the bottom. If you suspect that the bark contains parasites or fungi, pour some hot water over it or boil it a bit to destroy these nuisances.
The substratum for terrestrial orchids
It is much safer and simpler to buy the one sold for Cymbidium or boat orchids. You may add polystyrene for ventilation, if necessary.