Methods and Techniques for Selecting Orchid Growing Media

Chapter One, Principles

　　

To grow orchids well, the first issue you will encounter is which growing medium to choose. To choose a good growing medium, you must first understand the growth characteristics of orchids. We know that the stomata on orchid leaves are sunken, so respiration is incomplete and the roots must also help with breathing; orchids mostly grow in places rich in humus with loose soil; orchid growing sites mostly have dry soil and high air humidity, and orchid leaves absorb moisture from the air to make up for the shortcomings of the orchid roots. Therefore, when choosing orchid growing media, we should pay attention to the following principles:

　　

1. Loose and breathable. In the practice of growing orchids, we know that choosing granular growing media and discarding powdery growing media is because it creates a loose and breathable environment for the orchids, making it easier for the orchid roots to breathe.

　　

2. Moisture-retaining but not waterlogged. An orchid is a plant and needs moisture; but orchid roots are fleshy roots and cannot tolerate waterlogging. A good growing medium allows water to flow through immediately when watered, never accumulates water, and can still remain moist for a relatively long time.

　　

3. Clean and containing nutrients. Wild orchids have strong resistance, but after transplanting their resistance weakens and they are more susceptible to pests and diseases; the growth of orchids, like other plants, cannot do without various fertilizers. A clean growing medium that contains nutrients is a necessary condition for the normal growth of orchids.

　　

Chapter Two, Types

　　

According to the growth characteristics of orchids, and especially people's long-term practical experience in orchid cultivation, the growing media available for us to choose when cultivating orchids are diverse. Judging from the growing media widely used and sold on the market, they can roughly be divided into the following three major categories:

　　

1. Soil-type media. Mainly including mountain soil, pond mud, bamboo root soil, peat soil, and various types of humus soil, etc.

　　

This type of growing medium is the main material of traditional growing methods. Its advantages are moisture retention, nutrient content, easy availability, and low price; its disadvantages are that it easily compacts and accumulates water, does not dry easily after being thoroughly watered, and contains pathogens and easily breeds insects.

　　

(The Sichuan Xiantu currently sold on the market and some artificially made granular soil are no longer soil media in the traditional sense; this will be discussed later.)

　　

2. Organic-type media. Mainly including bark, rotten wood, coconut coir, wood chips, sugarcane bagasse, peanut shells, snake wood, palm fiber, and moss-type plants, etc.

　　

The main advantages of this type of growing medium are moisture retention, breathability, and after rotting it can provide organic fertilizer for orchids, which is beneficial for orchid root growth; the disadvantages are that it easily breeds insects and pathogens, and especially during the process of decomposition and rotting it gives off heat and harmful substances, which can easily burn orchid roots.

　　

3. Hard growing media. Mainly including pond foundation stone, Zhijin stone, volcanic stone, pumice, perlite, crushed brick pieces, and ceramsite, etc.

　　

The selection of this type of growing medium is the result of people's continuous exploration and reform in the practice of orchid cultivation. Its advantages are that it is granular and not easily broken down, clean and does not breed insects, has good breathability and does not compact, and does not accumulate water; its disadvantages are that it dries easily, contains no nutrients, and if the particle size is not chosen properly it is unfavorable for orchid root growth.

　　

Chapter Three, Selection

　　

In summary, the growth characteristics of orchids provide us with convenience in selecting orchid growing media. However, orchids are living things, and they will live for a long time in the small environment we choose for them; whether they grow well will be determined by whether we can provide a good environment and management. The selection of orchid growing media is an important part of the orchid growth environment. People often say: "Choose the right growing medium, and you are halfway to success in growing orchids," so we must never take it lightly. Faced with so many orchid growing media, how exactly should we choose? The practice of our predecessors and modern orchid growers has proven that as long as it conforms to the growth characteristics of orchids, any kind of growing medium can grow orchids well; the key is that different growing media are suitable for different environments, different pots, and different management. At present, in China's orchid circles there are three major schools in the selection of main growing media: the traditional soil-type growing method mainly in Yunnan, Guizhou, Sichuan, and other places; the hard growing medium method mainly in Guangdong, Fujian, Taiwan, China, and other places; and the mixed growing medium method mainly in Jiangsu, Zhejiang, Shanghai, and other places. Below, the selection of growing media and matters needing attention for these three growing methods are discussed separately.

　　

One, the traditional soil-type growing method.

　　

As the name implies, this growing method is to choose soil-type growing media and use traditional cultivation methods to grow orchids. In "Types" we have already analyzed the advantages and disadvantages of this type of growing medium, so when choosing this type of growing medium to grow orchids we should pay attention to the following matters:

　　

1. Use granular material as much as possible, sieve out the powdery material, and the soil must not be too sticky; if it is too sticky, a small amount of coarse sand, wood chips, bark, and the like can be mixed into the soil to improve the soil properties and soil quality.

　　

2. For pots, choose breathable, open-mouthed clay pots or sweating clay pots; a drainage layer must be placed at the bottom of the pot to prevent soil from clogging the drainage holes and causing water accumulation.

　　

3. In daily management, "dry growing" should be the main approach, that is, when watering we must grasp the principle of "do not water until dry, mainly keep moist; better a little dry than too wet." However, we must also pay attention to preventing the phenomenon of drying from the bottom of the pot upward, that is, watering must be thorough.

　　

4. Since the soil medium we choose contains a large amount of humus, there is no need to add base fertilizer; ordinarily we can choose to apply fertilizer by topdressing, and at the same time we must do a good job of insect killing and sterilization to prevent pests and diseases from attacking the orchids.

　　

5. The place where orchids are placed should be a well-ventilated site, such as an open or semi-enclosed place like a courtyard or balcony; ordinarily the orchid pots can be raised off the ground so that the orchid pots are in an environment ventilated on all sides, and the air humidity can be relatively lower.

　　

Two, the hard growing medium method.

　　

Using various hard growing media to cultivate orchids is a cultivation method that has become popular in China in the past ten-plus years. Compared with the traditional soil-type growing method, the greatest advantage of this growing method is that it facilitates our daily management and speeds up the growth rate of orchids. But it also has very obvious defects. Therefore, when we choose this type of growing medium to grow orchids, we must not ignore the following matters:

　　

1. Since this type of growing medium itself is usually granular in varying sizes, when choosing it we can generally select large particles like broad beans and small particles like soybeans. Particles that are too large are unfavorable for orchid root growth, while particles that are too small are unfavorable for breathability. When planting, if the orchid roots are thicker, more large particles can be placed; if the orchid roots are thinner, more small particles can be placed.

　　

2. In daily management, the "wet growing" method can be used to cultivate orchids, that is, keeping the growing medium moist frequently. However, we should still follow the principle of using different watering methods according to differences in pot material and differences in the strength or weakness of orchid seedlings, and must never overwater.

　　

3. This type of growing medium itself contains no nutrients, so artificial fertilization is needed to ensure the normal growth of orchids. We should pay attention to applying different fertilizers according to the different growth stages of orchids; ordinarily we can use a method combining topdressing and base fertilizer. For base fertilizer, some slow-release granular fertilizer should be chosen; for topdressing, the principle should be "dilute, light, frequent."

　　

4. This growing method is suitable for environments with relatively high air humidity and gentle breezes; ordinarily orchids should be placed in enclosed or semi-enclosed places, such as orchid fields, orchid sheds, enclosed balconies, or indoors. Some snake wood shavings or sphagnum moss and the like can be placed on the surface of the pot to keep the granules on the pot surface moist.

　　

5. When using it, we can mix a small amount of organic growing media such as bark and coconut coir into this type of growing medium to improve its defect of drying easily, and at the same time it can also provide certain nutrients to the orchids.

　　

Three, the mixed growing medium method.

　　

Since various growing media all have their own defects, using a single growing medium to cultivate orchids not only requires a certain environment and conditions, but also requires some targeted management measures in order to grow orchids well and strong. The emergence and use of the mixed growing medium method can be said to be a great advance in the history of orchid cultivation. This growing method is to mix several growing media from the soil-type, hard, and organic categories to prepare a new growing medium for cultivating orchids. Its greatest advantage is that during the preparation process we can increase or decrease the various growing media according to our own environment, pots, and management methods, so as to meet the needs of orchid growth and our own management. Likewise, when using this type of growing medium we need to pay attention to the following matters:

　　

1. Which several growing media we choose in the preparation and in what proportions depends on our own environment and the pots used; we can first choose a few and try growing. Generally speaking, in an open environment or a well-ventilated semi-enclosed environment, where breathable clay pots or sweating clay pots are ordinarily used, more soil-type and organic-type growing media can be used and less hard growing media can be used; if it is an enclosed or semi-enclosed environment with relatively high air humidity, more hard growing media and organic-type growing media can be used and less soil-type growing media can be used.

　　

2. Since this type of growing medium contains a certain amount of nutrients, ordinarily less or no base fertilizer can be applied, and topdressing should be the main method, following the principle of "light fertilizer applied frequently."

　　

3. The soil-type and organic-type growing media we choose when preparing this type of growing medium may contain pathogens and pests, so before preparation they must be sterilized and disinfected by chemicals or high temperature. At the same time, organic-type growing media easily produce heat and harmful substances during the process of rotting and decomposition, so before use they can be soaked in water for several months and then treated at high temperature in a microwave oven to solve this problem.

　　

4. When preparing this type of growing medium we often use some artificially made granular soil. This type of granular soil indeed has many advantages, but it also has many problems. For example, some use adhesives harmful to orchids, some cannot withstand soaking in water, some contain saline-alkaline components, some have too much nutrient content...... We should choose cautiously. After use, the "Hewang" brand Xiantu produced in Sichuan can serve as the first choice for this type of granular soil, except that before use it needs to be soaked for more than twenty-four hours.

　　

Orchid cultivation, like anything else, contains a great deal of knowledge; we must only observe more, think more, learn more, and practice more in ordinary times. Whether the selection of growing media in orchid cultivation is correct or not is of vital importance. I hope this article can be of some help to everyone.