The Role of Soilless and Soil-Based Cultivation of Orchids and Common Misconceptions

After exchanging a few pleasantries upon meeting, orchid enthusiasts will ask each other about theirorchidsand how well they are growing and what varieties they have acquired. As the conversation goes on, it quickly turns tocultivationsubstrate issues. Many orchid enthusiasts casually use the popular term "soillesscultivation." In reality, most of them are using "hard planting media" mixed with "Xiantu" and other machine-made granular types. What they do not realize is that "Xiantu" and similar machine-made granular soils are simply "peat soil" that has been sterilized at high temperature and then machine-formed into granules, and of course, a binder also plays a role in this process. Strictly speaking, this type of "planting medium" is "granular planting medium" and cannot be called "soillesscultivation" or "soil-based cultivation." After the "soilless cultivation" that is popular abroad was introduced to China, several versions have appeared (in fact, soilless granular cultivation was advocated and used as early as the Song Dynasty, and in a certain later year it was introduced abroad along withorchidseedlings; now, just like re-imported orchids, this technique has also been re-imported): 1. "Hard planting medium" cultivation This method uses various "hard planting media" such as "Zhijinshi, Emperor Stone, sea pumice, red jade stone, volcanic stone, weathered stone, perlite, water-accumulated stone," etc., combined with "bark and snake wood (or used alone as a single medium) for mixed planting." These "media" have all been sterilized at high temperature during production, so they are very clean. In addition, there are inexpensive and readily available materials such as "ceramsite, tile fragments, and brick fragments." The advantages of these "inorganic media" are that they make it easy to prevent and controlpests and diseasesand have good "aeration and drainage." The disadvantage is that they contain no fertilizer components or trace elements whatsoever, so full-element fertilizers must be added manually to promoteorchidgrowth. "Bark" and "snake wood" are organic materials that can slowly decompose during cultivation and release a small amount of nutrient elements. 2. "Nutrient solution" cultivation This "nutrient solution" is specially formulated according to the different nutrient elements orchids absorb at various growth stages, combined with greenhouse cultivation. The advantages are fast plant growth, a high "maturity rate," and good "appearance" (meaning many leaves with sealed tips). The disadvantages are that the plants are overly tender, commonly known as "hydroponic seedlings"; mature plants have small pseudobulbs (due to overly fast growth); and the roots are typically bean-sprout-like roots, showing a snow-white, plump, round, smooth, and vertical appearance. If switched to "hard medium" or other "media," the "adaptation rate" is low. Therefore, orchid enthusiasts generally will not choose such seedlings unless they cannot tell the difference. 3. "Soft planting medium" cultivation This type is mainly based on "sphagnum moss, coconut coir," etc., supplemented by foamed plastic fragments. This "medium" is mostly used for tropical "Cymbidium orchids" or "Cymbidium sinense." This category should be classified as a mixture of "organic" and "inorganic." The advantages are that it easily promotes new growth and root development with fast growth speed. The disadvantages are that it holds water too strongly and contains few fertilizer components, so full-element fertilizers must be added manually to promote orchid growth. The plants grow overly tender, but this is better than "hydroponic seedlings." 4. Mixed cultivation of "inorganic" and "organic" granules This point should be separately classified as "neutral medium." The so-called "inorganic granules" are the "hard planting media" mentioned above, and "organic granules" such as "Xiantu" and the recently promoted "Huangtu" and other machine-made soils. Items 1, 2, and 3 above belong to true "soilless cultivation," while this item 4 should be classified as "granular planting medium" and cannot be called "soilless cultivation." This should be clearly distinguished. The advantage is that it combines the strengths of the above "hard planting media" and "soft planting media" while compensating for their weaknesses. This combination of making up for each other's shortcomings will allow orchids to grow even better. The four major categories of "media" above have all been sterilized and disinfected at high temperature during production (the advantage of foamed plastic is that it is not prone to harboring pathogens, and since it is plastic, it does not require high-temperature sterilization). Therefore, there is no need to worry about carrying pathogenic bacteria. Due to different cultivation purposes, choices also differ. For example, those doing "tissue culture seedling cultivation" must choose "nutrient solution" or "soft medium" for cultivation and rejuvenation. "Hard inorganic media" mixed with organic "bark and snake wood" is also widely used in orchid cultivation. If mastered properly, this type can shorten the time to produce commercial seedlings. In fact, at present, the most commonly used among domestic orchid growers is still "hard granular medium" mixed with "neutral granular medium" (this has also been developed through the practical experience of many orchid enthusiasts in cultivation). This type of "medium" has comprehensive nutrient elements, long "water retention" time, and good aeration. As the duration of use increases, good soil-based granules will gradually soften, but they will absolutely not decompose into powder and then become compacted. Low-quality soil-based granules are the exception, as such granules use excessive amounts of binder, which makes it difficult for water to penetrate. As a result, they lose the advantage of soil retaining nutrient elements, and instead make it difficult for orchid enthusiasts to judge water management. The "medium" formulated as described in point 4 above should be very scientific. In addition to the advantages mentioned above, it also produces plump pseudobulbs and high-quality commercial seedlings. The most notable feature is that theflower'sfragrance is rich, deep, and lasting (according to widespread reports from orchid enthusiasts, the fragrance is more delicate and lasting compared to soilless cultivation). Commercial seedlings cultivated in such "medium" easily adapt after repotting, which is also one of the primary reasons orchid enthusiasts prefer it. It solves the shortcomings of "orchid mud and peat soil" in terms of aeration, compaction, and containing pathogens. It inherits the trace element content advantages of "orchid mud and peat soil." Through this complementary advantage, the "trace element deficiency" of "hard planting media" is also thoroughly solved, and moisture retention is also increased. In short, in the process of formulating and using "media," one should practice more, record more, and summarize more. This is the first step toward "success being in sight." Note: Machine-made granular soil contains an appropriate amount of binder, so it must be soaked thoroughly before use. Remember this! Remember this! Purpose: For beginner orchid enthusiasts' reference. Wan Yunkun