How to grow orchids? Beginners can easily grow them well by mastering these methods
Compared with other flowers, orchids are indeed somewhat harder to grow. The difficulty lies in the fact that orchid roots are relatively sensitive to water and are easily "drowned" or "thirsted to death." When the state of the growing medium being too wet or too dry lasts longer than the orchid roots can tolerate (to be precise, when the period of oxygen deficiency or water deficiency in the growing medium exceeds what the orchid roots can endure), it will cause root rot or hollow roots; if it lasts even longer, the root problems will be reflected on the leaves, and the plant will eventually turn yellow and die.
Because the pseudobulbs of the orchid itself contain water, and because whether the orchid roots are rotted or hollow, their remaining parts still retain some ability to absorb water, the orchid can still linger for a while even if there is a problem with the roots, and problems are not easily detected in time from the above-ground parts of the plant.
In fact, orchids are more often "drowned," that is, due to improper selection and blending of the growing medium, too strong water retention, or too frequent watering, the growing medium stays constantly soggy. When this overly wet state lasts beyond what the orchid can tolerate, the orchid roots rot and the plant eventually dies. In addition, some people, having heard that orchids "fear" water, water them very seldom, and as a result overcorrect and the orchid is "thirsted to death"; such cases also exist. It can thus be seen that whether the water content in the growing medium can be properly controlled is the key to success or failure in growing orchids.
Why can't orchids be grown in ordinary soil?
Let us first analyze the changes in the dry-wet state of soil after watering: "wet" -> "somewhat wet" -> "moist" -> "somewhat dry" -> "dry." Among these, "wet," "somewhat wet," "dry," and "somewhat dry" are all unfavorable to orchid root growth; only "moist" is most suitable for orchid growth. Because ordinary soil, after watering, remains "wet" or "somewhat wet" for too long, exceeding what the orchid can tolerate, tragedy naturally occurs, and therefore ordinary soil is not suitable for growing orchids.
It can thus be seen that shortening as much as possible the time the growing medium spends in the "wet" and "dry" states, and prolonging the time it spends in the "moist" state, is the fundamental goal of orchid cultivation. Whether it is the selection and blending of the growing medium, the choice of orchid pot (the size and material of the orchid pot also greatly affect changes in the water content of the growing medium), or watering, all are carried out around this goal.
From this it can also be seen that the water-retaining or water-draining properties of the growing medium itself determine to a very large extent the changes in its water content, and even determine success or failure in growing orchids. It can be said that watering is the external cause determining changes in the water content of the growing medium, while the growing medium is the internal cause. To control the water content of the growing medium well, the prerequisite is that the growing medium must be properly selected and blended.
How can one judge the orchid-growing effectiveness of a growing medium?
The so-called orchid-growing effectiveness of a growing medium is also its root-growing effectiveness. If the orchid roots are grown well, the above-ground parts (leaves, shoots, etc.) will certainly grow well; if the orchid roots are not grown well, the above-ground parts will not be good either. Therefore, from the growth condition of the above-ground parts, one can judge the growth condition of the orchid roots.
For example, after the orchid is potted, if it regains vitality in 1 to 3 weeks (recovery is fast in spring and autumn, slow in summer and winter), the leaves are glossy, new seedlings grow (noticeably taller), new shoots emerge (as in spring), and the leaves feel resilient when brushed by hand, it shows that the orchid roots are growing well, the growing medium is relatively ideal, and management (mainly watering) is also on point.
If, for a period after potting (about 1 month), the leaves have no gloss, new seedlings stagnate in growth (stunted seedlings), new shoots do not emerge or emerge only sparsely (in spring), the leaves feel limp when brushed by hand, and black spots easily appear on the leaves when the temperature is slightly high, then it shows that there must be a problem with the orchid roots, and the growing medium may not be ideal. In this case, the pot must be turned out. If possible, turn out the pot at the time when watering would normally be due (for example, if water is normally given once every 5 days, turn out the pot before watering on the 5th day).
If the growing medium is found to be soggy and the roots have all or partly turned black, it shows that the growing medium retains water too strongly, and some air-permeable, water-draining material should be added to it, such as granular growing medium, tree fern, decomposed peanut shells, etc.; of course, if the water retention and drainage properties of the growing medium already feel relatively ideal, then without improving the growing medium, simply appropriately extending the watering interval can also solve the problem. If, when the pot is turned out, the roots and growing medium are found to be in a dry state, or hollow roots have even appeared, then some material with strong moisture-retaining properties should be added to the growing medium, such as leaf mold, perlite, etc.; if the growing medium feels relatively ideal, then shortening the watering interval will also do.
It is somewhat difficult to judge whether the underground part (roots) is healthy from the growth condition of the above-ground part of the orchid plant; the simplest and most intuitive method is still to turn out the pot and look at the roots. There are two kinds of turning out the pot: surface turning and full turning. Surface turning means removing part of the growing medium from the pot surface, to a depth of 5 to 10 cm, to observe the growth state of the roots around the pseudobulbs and at the surface layer of the growing medium. If new roots have grown or the root tips of old roots have crystal-clear "crystal heads," it shows that both the growing medium and management measures are relatively ideal; if there are no new roots, or the root tips of old roots have turned black or even rotted, it shows that there is a problem with the growing medium or watering. If you want to understand the growth state of all the roots, then you can only do a full turning. Whether surface turning or full turning, be careful to damage the roots as little as possible, especially the root tips. Although turning out the pot is a bit troublesome, it is the most intuitive and accurate method for understanding the orchid-growing effectiveness of the growing medium, and it is also a necessary path for beginners to accumulate experience.
The orchid is neither dead nor growing new seedlings, just half-dead; what should be done?
As stated earlier, if the above-ground part of the orchid does not grow well, there must also be a problem with the orchid roots. If the above-ground part is half-dead, it shows that the underground part is in a bad situation - most of the roots are growing poorly, and perhaps only one or two roots remain to sustain the plant's life. In this case, the pot must be turned out and the growing medium replaced with an ideal one.
How can one blend a good growing medium oneself?
There are many materials that can be used for growing orchids, and each place can use local materials, but to blend an ideal growing medium, the following principles must be followed:
1. The physical structure of the growing medium is ideal, air-permeable, and water-draining. Use granular growing medium; there are certain gaps between the granules, so natural air permeability and water drainage are good. If using powdery growing medium such as leaf mold, add perlite, tree fern, and granular growing medium, etc., so that it becomes fluffy.
2. The chemical composition of the growing medium is reliable, with no harmful components. Some organic growing media, such as peanut shells and pine bark, must be decomposed; otherwise, after use they will decompose substances harmful to orchid roots.
3. The growing medium has good moisture-retaining properties, both draining and retaining water. An ideal growing medium should spend a short time "wet" and a long time "moist." That is, after watering, because the physical structure of the growing medium is good (there are gaps between the particles), a large part of the water drains away, and afterward, because the growing medium itself has absorbed a certain amount of water, it can maintain the "moist" state for a relatively long time, and then slowly change from "moist" to "dry" (note: the growing medium does not suddenly change from "moist" to "dry," but changes slowly, that is, the growing medium spends a relatively long time in the "somewhat dry" state between "moist" and "dry").
This has three major advantages: first, the growing medium spends a short time "wet," avoiding root rot; second, the growing medium remains "moist" for a relatively long time, creating favorable environmental conditions for orchid root growth; third, the growing medium remains in the "somewhat dry" state for a relatively long time, and the ideal watering time is when the growing medium is in the "somewhat dry" state; obviously, watering is then easier, and it does not matter much if it is one or two days earlier or later. If the growing medium does not retain moisture well and quickly changes from "dry" to "wet," the "somewhat dry" period is relatively short, and the watering time must be judged relatively accurately to ensure that the watering time falls within the period when the growing medium is in the "somewhat dry" state; this is quite difficult, and watering is easily too early or too late, which is unfavorable to orchid growth.
In short, a growing medium with good moisture retention can not only avoid root rot in orchids, but also reduce the difficulty of watering. Of course, to blend a growing medium with ideal moisture retention, before selecting and blending, one must have a full understanding of the water-retaining and water-draining properties of each growing medium and the fluffy effect it can produce in the mixed growing medium.
As long as these principles are followed, a good growing medium can be blended. Of course, whether a growing medium is good or not can only be known after use. It is worth noting that after blending a growing medium you think is ideal, do not rush to repot all orchids with the new growing medium; you must first try it on one or two pots, and only after the effect is verified should you use it on a large scale.
Is there an orchid-growing formula that is easy to source or buy and has ideal results?
1. Classic formula
65% Kanuma soil + 35% Sendai soil. (Volume ratio, the same below)
This formula is widely used and has been relatively generally recognized by orchid enthusiasts. With this formula, the growing medium is air-permeable and water-draining, orchid roots generally will not have problems, and growing orchids is easy to succeed with. Note: commercially sold Sendai soil varies greatly in quality, so buy reliable quality; before use, both must be soaked through, that is, only when the granules are broken open and already moist inside can they be used.
With this formula, because nutrients are insufficient, about 30 granules of Osmocote or 10 to 30 granules (depending on pot size) of Magic Fertilizer can be placed on the pot surface. In the south, where balconies have relatively strong dry winds, the orchid pot can be slightly larger, and a layer of sphagnum moss can be placed on the pot surface to retain moisture.
2. Simple formula
50% leaf mold + 50% perlite.
For leaf mold (or mountain surface soil), you can take the surface soil under broad-leaved forest containing dead branches and fallen leaves (which also contains soil). This kind of soil is loose; when squeezed by hand it forms a ball, and when the hand is opened the soil disperses. Add an equal amount of perlite, and the leaf mold becomes fluffier and will not compact. Perlite has a very strong fluffy effect, retains moisture well, and is low in price, making it an ideal growing medium. On this basis, you can also mix in 20%-50% of other granular growing media, choosing one or several of the following: coal cinder granules (the granules left after sieving the powder out of coal ash), decomposed peanut shells, decomposed pine bark, brick granules the size of soybean grains, small-grade akadama, small-grade Kanuma soil, etc., for even better results.
It is worth mentioning that the leaf mold formula developed by Lin Shengzhou is easy to source, low in cost, and ideal in growing results. Its formula is: 50% leaf mold + 50% sandy clay soil. Sandy clay soil is a kind of soil half differentiated into sandy quality, not easily sticky.
Because leaf mold is rich and abundant in nutrients, no fertilizer is needed, and the seedlings grown are relatively strong. Particular attention should be paid to the fact that some beginners are always afraid the orchid will be "starved to death" and like to apply all kinds of fertilizers to orchids, and the orchids are often "rettingly killed" by fertilizer.
3. Commercial growing medium
If you feel that blending the growing medium yourself is troublesome, then you can buy ready-made commercial growing medium. Its composition is:
1 part leaf mold + 1 part perlite + 1 part tree fern fiber + 1 part akadama + 1 part Sendai soil + half part coconut coir (all refer to volume).
After many years of trials, orchids cultivated with this growing medium have good roots and strong seedlings, with good results.
Orchid enthusiasts from other places can select and blend it themselves according to this formula; they can also adapt to local conditions, use local materials, and make appropriate improvements to the formula or substitute ingredients.
When orchids develop black spots, it is mostly anthracnose, and there are mainly two underlying reasons:
1. The orchid seedlings are not strong enough, and the resistance of the orchid seedlings is relatively weak. The root cause is still that the growing medium is not ideal and the orchid roots are not growing well, so effort must still be put into the growing medium.
Poor roots lead to black spots on leaves
2. The orchid is exposed to the sun at relatively high temperatures or the environment is relatively stuffy and hot. After the temperature exceeds 28°C, the orchid should be shaded; at the same time, in hot seasons, the environment should be ventilated, and stuffy heat must be avoided; the key is still to improve cultivation conditions, which is the fundamental solution. When necessary, spray 800-fold solution of Shibaogong (oligomycin) or Score to curb the development of the disease.
When orchid leaves turn yellow, there are mainly two reasons:
1. Leaf yellowing caused by natural aging. In spring and summer, orchid metabolism is active, new shoots continuously emerge, and at the same time some old seedlings that have grown for many years also wither and die. This kind of yellow leaf from "old death" has three characteristics: first, it occurs on old pseudobulbs; second, the pseudobulbs show nothing abnormal (such as turning black or rotting); third, leaf yellowing generally starts from the outer leaves of the orchid plant and then moves to the inner leaves, from the leaf tip to the leaf base. In addition, there will be no black spots on the yellow leaves.
2. Leaf yellowing caused by disease. The orchid plant develops stem rot, bacterial soft rot, or white silk disease. This kind of yellow leaf mostly occurs on new seedlings; leaf yellowing develops from the central leaf outward to the outer leaves and from the leaf base toward the leaf tip, and there are often abnormal conditions on the pseudobulbs (such as turning black and rotting, etc.). In this case, the diseased plants must be broken off, and the roots and pseudobulbs of the remaining healthy plants should be soaked for 1 hour in a broad-spectrum fungicide (such as carbendazim, hymexazol, etc.), then repotted with new growing medium.
By grasping the key points of orchid growing, you can absolutely grow orchids well with ease:
1. Go to the nearby mountains and take some loose leaf mold or surface soil with dead branches and fallen leaves (it is fluffier only with dead branches and fallen leaves), and according to the method described in the above "simple formula," mix in an equal amount of perlite; if perlite is not available for the time being, you can mix in an equal amount (by volume) of sandy clay soil, or mix in twice the amount of crushed brick granules or coal cinder, etc. (mixing two or more is better). Blending a fluffy, air-permeable, water-draining growing medium is the key to growing orchids well, and it must be done carefully.
2. A medium-sized orchid pot is fine. If it is too large, the growing medium does not dry easily and can easily cause root rot; if it is too small, the growing medium dries too easily and is hard to manage.
3. Place the orchid on a south-facing balcony or in a courtyard (do not put it on a north-facing balcony or keep it indoors for a long time). In spring and winter, let it get more sunlight; in summer and autumn, when people feel uncomfortable in the sun, do not let the orchid be directly exposed to the sun. No fertilizer is needed.
4. Water when the growing medium is dry. If you are not sure, you can dig two or three cm deep into the pot surface growing medium; if it is dry there, water immediately; if it is not dry yet, water after another day or two. When watering, water the whole pot thoroughly, watering for a longer time, so that all the growing medium "takes in" water.
5. In the north, when the winter temperature approaches about 3°C, be careful to move the orchid indoors to avoid cold damage; south of Fujian, orchids can overwinter safely outdoors in winter.