How to fertilize stump bonsai scientifically? These methods you need to master

  The fertilization method for stump bonsai is very important. If too much fertilizer is applied, the branches and leaves grow excessively; if fertilizer is lacking, the branches become thin and weak, the leaves turn yellow, and the plant is prone to pests and diseases. So here are three scientific fertilization methods:

  First, according to quantity. The amount of fertilizer for stump bonsai should follow the principle of small amounts applied frequently. Each application should be small and dilute; large stumps and bonsai with luxuriant branches and leaves should be given appropriately more fertilizer; otherwise, less should be applied. Generally, during the long vigorous growth period from the Beginning of Spring to the Beginning of Autumn, a dilute fertilizer solution should be applied once every 10 days, that is, 7 parts water and 3 parts fertilizer. Liquid fertilizers such as 4—6% monopotassium phosphate, Chunquan 883, Feilibao, and Huimanfeng can also be used for foliar feeding, which gives even better results. After the Beginning of Autumn, fertilizer can be applied once every 20 days, and the amount should be gradually reduced. After the Beginning of Winter, no more fertilizer should be applied;

  Second, according to fertilizer type. Nitrogen fertilizer can promote luxuriant plant growth and more flower buds. Commonly used nitrogen fertilizers include soybean cake, ammonium sulfate, urea, and high-temperature decomposed human and livestock manure; phosphorus fertilizer promotes bright flower colors and plump fruits, such as superphosphate and crushed bone meal. Foliar spraying of monopotassium phosphate, etc.; potassium fertilizer promotes well-developed root systems, material transport, and sturdy plants. Commonly used ones include potassium sulfate, potassium chloride, plant ash, etc., and foliar spraying of monopotassium phosphate solution can also be used. At the same time, fertilizer should be applied separately according to the plant's growth condition, and flexibly adjusted according to the tree species' characteristics and growth condition.

  Third, according to timing. For newly planted stump bonsai, those just potted, or those newly repotted with fresh soil, since the root system has been damaged, fertilizer may temporarily be withheld. Wait until the following spring or early summer, when the potted tree grows vigorously, to apply more fertilizer; after autumn begins, as the potted tree grows slowly, less fertilizer should be applied; in winter, when the potted tree has entered dormancy, fertilization should stop. Fertilizer should not be applied on rainy days or around noon during the high temperatures of midsummer, because fertilizing on rainy days easily causes nutrient loss and can easily damage the root system; and at high temperatures, rapid water evaporation causes the fertilizer solution concentration to become too high and burn the roots. Fertilizing on cloudy days or in the evening is best. If the potting soil is slightly dry, first remove weeds from the pot, loosen the soil, and then apply fertilizer. This helps the fertilizer water penetrate the soil, promotes faster decomposition of the fertilizer for absorption and use, and at the same time avoids fertilizer damage.

  To care well for stump bonsai, in addition to having good light and humidity conditions, the most critical thing is how to accurately control the amount of fertilizer and water, which is what people often call "restraining" and "releasing." Because stump bonsai have different fertilizer requirements at different growth stages, different maintenance periods, different varieties, and different appreciation purposes, fertilization must be targeted and treated differently. Not only must the appropriate amount and concentration be accurately controlled, but the ratio of nitrogen, phosphorus, and potassium must also be appropriately adjusted. Only in this way can you take the initiative in maintenance. Let new stumps grow satisfactory branches that meet the modeling conditions as early as possible, take shape as soon as possible, and make already formed stump bonsai grow with small, deep green, glossy leaves, thick and strong branches and trunks, and abundant flowers and fruits. Here are a few views on the "restraining" and "releasing" of fertilization for stump bonsai.

  (1) The "restraining" and "releasing" during the stump cultivation period

  Before a new stump has truly survived and grown enough robust (woody) new roots, not only should fertilizer be "restrained," but it is best not to fertilize at all, at least not before summer. This is because in the early growth stage of a new stump, its body still stores certain nutrients, and the potting soil also contains a small amount of fertility. The early growth of the new stump does not consume much fertilizer, and these nutrients are enough to sustain its growth for a period. Also, because in a short time the new roots of the new stump are still in the budding stage, a small number of the original old roots will rot and die, and a supply system sufficient to support the entire stump has not yet formed. If fertilizer and water management during this period is handled improperly and is even slightly too concentrated, it may cause the newly sprouted tender roots to be burned and rot, and the original old roots to rot more severely. In serious cases, the new stump may die before surviving the summer. Therefore, for new stumps, fertilizing after autumn is better, as it is safer.

  (2) The "restraining" and "releasing" during the transition period

  The transition period refers to the period after a new stump has survived for one year, but before shaping and potting have begun, or during only the basic framework branch positioning and rough shaping stage. During this period, effort should be put into "releasing." Without damaging its root system, or by deciding concentration and amount according to the growth effect after fertilization, gradually increase the amount of fertilizer and water as much as possible. At the same time, foliar feeding can be adopted to give some valuable branches "special treatment" through local spraying. As long as it can bear it, seize the opportunity to increase fertilization, but you must carefully observe the growth of its branches and leaves at all times. Do not blindly apply concentrated fertilizer; safety comes first.

  Because during this period the stump is still in the stage of growing its "body," many branches are still far from reaching the standard and quantity required for shaping. Therefore, only by providing sufficient fertilizer and water can the branches be helped to reach the standard required for production sooner, thereby shortening the time needed for shaping and formation.

  (3) The "restraining" and "releasing" of formed stump bonsai

  After stump bonsai production is completed and potting and shaping are done, the traditional practice is to "restrain" fertilizer as much as possible to prevent the leaves from becoming too large, losing proportion, and affecting the appreciation effect. But I think it is better to focus on appropriate "releasing," with appropriate "restraining" as a supplement. This is because after most stumps are maintained in display pots for a period, their leaves will naturally gradually become smaller, and there is no need to deliberately adopt the method of "restraining" fertilizer to control leaf size. It is best to use other methods such as leaf picking to control it. Because the display potted period is very different from the field planting and stump cultivation potted period, especially now that people commonly use shallow pots, the soil environment for stump bonsai growth is much worse than during stump cultivation. Not only is there less soil and limited nutrients, but many roots cannot extend and are even exposed on the surface of the potting soil, unable to absorb enough nutrients, which also limits their growth speed and leaf expansion. Therefore, for formed stump bonsai, it is better to supplement fertilizer in a timely manner and carry out normal care. Restraining fertilizer to reduce leaf size can only cause malnutrition in the stump bonsai, gradually weakening its growth and making it listless. Even if you want to control certain stump bonsai with excessively vigorous growth and overly large leaves, you can only restrain fertilizer for a short period in the early stage when spring growth has just sprouted, to prevent leaves and pine needles from expanding and lengthening without limit. At other times, it is better to use normal fertilizer and water management, timely supplement the nutrients it needs, and maintain its normal healthy growth. This is especially true for flowering and fruiting stump bonsai: if potassium and phosphorus fertilizers are lacking during the bud stage and fruit enlargement stage, it is difficult to ensure normal flowering and fruiting.

  (4) The "restraining" and "releasing" of special stump bonsai

  So-called special stump bonsai refers to those whose original stump is not very robust, with a relatively large area of decay and rot, and some even with only half of the living bark water-conducting line remaining. For such stump bonsai, fertilizer and water management from the very beginning of stump cultivation to after shaping and formation must always be prudent and careful. Because the root system of such stumps is fewer than that of normal stump bonsai, and their constitution is weak and resistance poor, survival is very difficult. Fertilizer and water management can only proceed step by step, neither releasing nor restraining, with the main goal of ensuring normal growth. If released improperly, it will damage the roots and lead to death; if fertilizer is restrained too tightly, it will prevent the remaining cortical water-conducting line from further thickening and expanding, and it will gradually degenerate and shrink. If there is even a slight mistake in management, it can also lead to death by drying up.

  In short, the fertilizer and water management system for stump bonsai must adopt different countermeasures according to the different conditions of each stump bonsai. Never apply the same method to all, and even less should you blindly apply concentrated fertilizer. That is more harmful than lack of fertilizer; just one time can destroy the entire stump bonsai.