How to Grow Stump Bonsai? A Detailed Guide to Daily Care and Management

Growing Techniques Jan 1, 1970 0 views

Stump bonsai is primarily based on flowering and woody plants. The quality of a stump lies not in whether the chosen tree species is rare or precious, nor in the size of the material used, but in whether its natural form has potential for development, and in the artistic conception and charm embodied in the creator's styling. Stump bonsai is a miniature of ancient mountain stumps, and above all one should learn from nature. The ancient cypress with gnarled branches stretching across the sky, its momentum like a roaming dragon, its trunk twisted and spiraled; the vigorous pine with large branches extending sideways, hanging upside down over cliffs, its foliage like clouds; the graceful nandina with soft spreading branches, brilliant flowers and fruit, elegant and refined - all are excellent models for creating stump bonsai.

1. Watering

Watering is one of the most important and most frequent measures in stump bonsai management. When a stump is planted in a pot, whether a deep pot or a shallow pot, the soil is always limited, and the water it contains is also limited. If water is not replenished by watering over a long period, the stump will wither from lack of water. Therefore, one should observe promptly and water according to the dryness or moisture of the soil to maintain soil moisture. Of course, watering must not be excessive either. If watering is excessive and the potting soil remains too wet for a long time, it can easily cause root oxygen deficiency and rot. At the same time, the amount of watering also depends on the specific tree species, seasonal changes, and whether the weather is cold or warm. Generally speaking, in summer or during drought, it is best to water once in the morning and once in the evening. In spring and autumn, water once a day or every other day. In spring when the stump begins to sprout, you may also water once in the morning and once in the evening as conditions warrant. During the plum rain season or on rainy days, watering is not needed, and attention should be paid to drainage. Sandy soil can be watered more, while clayey soil should be watered less. Watering can be done by spraying the leaf surface or by irrigating the roots. Generally the two are combined: first spray the leaf surface, then irrigate the roots thoroughly. Be careful not to give “half water,” which causes the surface of the pot to be wet while the inside of the pot is dry. Also, leaf spraying should not be excessive, as it can easily cause leggy growth of branches and leaves.

2. Fertilizing

The soil in the pot of a stump bonsai is limited, and therefore nutrients are also limited, so attention should be paid to supplementing fertilizer. Because of its artistic characteristic of showing the large within the small, stump bonsai should not be fertilized too much or too frequently. One must grasp the fertilizer concentration and types, and seize the right fertilizing season. The three essential elements for plant growth nutrients are nitrogen, phosphorus, and potassium fertilizers. Nitrogen fertilizer can promote the growth of branches and leaves of the stump; phosphorus fertilizer can promote the formation of its flowers and fruits; potassium fertilizer can promote the growth of the trunk and roots. Therefore, the choice of fertilizer should be determined according to the stump species and its growth condition.

If you need the stump to have luxuriant branches and leaves, you can apply more nitrogen fertilizer; if you need the stump to produce more flowers and fruits, you can increase the phosphorus fertilizer content; if you need the roots and trunk to be thick and well developed, you can apply more potassium fertilizer. Fertilization methods are generally divided into slow-release fertilization and quick-acting fertilization. Slow-release fertilization generally involves crushing and composting organic fertilizer, then mixing it into the soil in a certain proportion. When changing the soil, mix it into the pot and let it slowly provide nutrients. Quick-acting fertilization involves diluting organic fertilizer or chemical fertilizer and applying it according to the seasonal growth needs of the stump. However, note that it must not be too concentrated. Newly planted stumps are not suitable for this type of fertilization. Fertilizing on rainy days causes the fertilizer efficiency to leach away, with poor results.

3. Prevention and Control of Pests and Diseases

Disease appearing on branches and trunk: manifested in rot of the phloem and cambium of branches and trunk, occurrence of stem rot and cankers on branches and trunk, rotting of the branch and trunk surface, decay of the inner wood, and spots appearing on twigs. Usually Bordeaux mixture should be sprayed, followed by lime sulfur mixture, and the rotted parts should be scraped away.

Leaf diseases: Leaf diseases usually show symptoms such as yellow-brown or black spots, curled leaves, withering, and early leaf drop. They may be chlorosis, leaf spot disease, sooty mold, powdery mildew, and so on. For leaf spot disease, remove the diseased leaves and spray Bordeaux mixture; for chlorosis, spray the leaf surface with a 0.1-0.2 ferrous sulfate solution; for powdery mildew, spray with a 0.3-0.5 degree Beaume lime sulfur mixture.

Root diseases: When the roots of a stump bonsai age, they are prone to various root rot diseases or root nodule diseases caused by bacteria and fungi. Attention should be paid to disinfecting the potting soil and controlling the amount of watering.

Scale insect control: Scale insects are widespread and numerous in species. They are pests that suck the sap of the stump. After a stump is harmed by them, it is prone to sooty mold, showing poor growth, yellowing and withering of branches and leaves, and early leaf drop. Control methods, in addition to manually brushing them off and killing them, include spraying with a 1000-1500 times solution of 40% dimethoate emulsifiable concentrate, or a 1000-1500 times solution of 80% dichlorvos.

Red spider mite control: Red spider mites harm leaves by sucking leaf sap. After infestation, the leaves take on a gray mottled color and are caused to wither, yellow, and drop. The control method is to spray with a 1500-2000 times solution of 40% dimethoate emulsion or a 1000 times solution of 50% phoxim wettable powder.

Aphid control: Aphids are numerous in species and widespread in harm. Affected stumps generally have curled and drooping leaves, and in severe cases the leaf surface becomes dirty black, dry, and falls off. Control method: generally spray with a 2000-3000 times aqueous solution of 40% dimethoate, once a week. Or spray with a 2.5% rotenone 800-1200 times aqueous solution.

Pruning: Bonsai trees are still constantly growing. If allowed to grow naturally without suppression, it will inevitably affect the tree's form and styling and cause it to lose its artistic value. Therefore, timely pruning is necessary: shorten long shoots, thin out dense shoots, so as to maintain a beautiful tree form and appropriate proportions.

Pinching: For tree bonsai, in order to suppress its height growth and promote the development of side branches into a flat spread, the tender tips of the branch shoots may be pinched off.

Bud pinching: When many adventitious buds grow at the base or on the trunk of a tree bonsai, the buds should be pinched off at any time to avoid the sprouting of forked branches that affect the beauty of the tree shape.

Leaf removal: For foliage-appreciation tree bonsai, the ornamental period is often the period when new leaves sprout. For example, the new leaves of maple and pomegranate are red. Through leaf removal treatment, the tree can be made to sprout new leaves several times a year, bright and pleasing to the eye, improving its ornamental effect.

Branch pruning: Tree bonsai often produces many new branches. To maintain its beautiful styling, attention must always be paid to pruning. The pruning method should be determined according to the tree form. For example, for a cloud-layer style, the branches should be pruned into a flat and even shape. Generally, dead branches, parallel branches, crossing branches, and others that detract from beauty should all be cut off promptly.

Root pruning: When repotting, combine it with root pruning. Roots that are too dense or too long should be pruned. This can be considered according to the following situations. If the tree's new roots are poorly developed and the root system has not densely covered the bottom surface of the soil ball, then the original pot may still be used for repotting, and root pruning is not needed. For tree species with well-developed root systems, where the fibrous roots densely cover the bottom surface of the soil ball, a slightly larger pot should be used, the dense root system should be thinned, old roots removed, and a few new roots retained for repotting. For some old stump bonsai, when repotting, the roots may be appropriately raised to increase ornamental value. Also prune away old roots and portions of the root tips, and cultivate with loose, fertile soil to promote the growth of new roots.

Repotting and soil changing: After a bonsai tree has grown in a pot for many years, fibrous roots densely fill the bottom of the pot, making it difficult for water to penetrate and drain, and fertilizer is also not easily absorbed, which will affect the normal growth of the tree. At this time, it should be repotted and the soil changed. For repotting, the original pot may be used or a pot one size larger may be chosen, determined according to the size of the tree. Changing the soil can improve soil aeration and water permeability, increase soil nutrients, help the bonsai tree grow robustly, and improve its ornamental effect.

The soil for repotting a stump is mainly leaf mold, paddy field soil, mountain soil, and so on. When changing the soil, some nutrients may first be appropriately added to the soil so that they ferment and volatilize in the soil to become slow-release nutrients, thus allowing the stump to benefit slowly. As for grasping the soil pH, this should be determined according to the specific situation of the tree species. When repotting, generally first fix a screen or tile piece at the bottom hole of the pot, then add larger-grained soil to facilitate drainage, then place the stump, fill in finer-grained growing medium, tamp it firmly with a bamboo or wooden stick, and determine the amount of watering according to the tree species.

Repotting of tree bonsai can be determined according to the following aspects:

① Generally, small bonsai are repotted once every 1-2 years, medium bonsai once every 2-3 years, and large bonsai once every 3-5 years. In the case of old stump bonsai, repotting may be done once every several years.

② For tree species that grow vigorously and like fertilizer, repotting should be more frequent and the interval shorter; for tree species that grow slowly and require less fertilizer, repotting may be less frequent and the interval longer. Old stump bonsai of the pine and cypress type should not be repotted frequently.

③ Tree species with luxuriant branches and leaves and well-developed root systems should be repotted frequently. Repotting can be determined by the condition of root growth. When the potting soil is neither dry nor wet, turn the pot upside down and pat the bottom of the pot with your hand to tip out the tree together with the soil and roots. Check the condition of soil compaction and root distribution. If the soil ball is compacted and the root system densely covers the bottom surface of the soil ball, this indicates that repotting is necessary.

The time for repotting is best chosen during the tree's dormant period, mostly in early spring or late autumn. If a relatively large amount of original soil is retained, repotting can be done at any time without seasonal restriction. If most or all of the old soil needs to be replaced, then the appropriate repotting period should be strictly chosen.

4. Placement and Protection

The placement of stump bonsai should also be determined according to the characteristics of the tree species. Generally, it should be placed in a ventilated and light-transmitting location with a certain amount of spatial humidity. Insufficient sunlight, poor ventilation, and lack of a certain spatial humidity can cause the plant to turn yellow and dry out, leading to the occurrence of pests and diseases, and even death. However, some tree species prefer shade, and some stumps need a bit more sunlight, so measures such as shading or light blocking must be taken. For example, some evergreen broadleaf or non-broadleaf tree species such as boxwood, azalea, and camellia mostly prefer shade, while crape myrtle, ginkgo, and crabapple prefer sunlight, so this should be determined according to the specific situation. Some stump bonsai are also cold-tolerant or not cold-tolerant. For non-cold-tolerant stumps, in winter they generally also need to enter a greenhouse for maintenance and management, such as banyan and Fukien tea.

Winter Care and Management of Stump Bonsai

As the weather turns cold in winter, winter care and management of stump bonsai is particularly important. This article summarizes three key care points respectively: 1. Appropriate water, do not fertilize. 2. Do not prune, eliminate pests and diseases. 3. Maintain light, prevent cold and freezing.

1. Appropriate water, do not fertilize

In winter, watering should follow the principle of preferring dryness over moisture; do not water unless the soil turns white. Water at noon, and it is best to water thoroughly at one time. Do not water in the evening, otherwise it is prone to freezing damage. For coniferous types, wax-leaf types, and landscape trees with thick dense foliage and verdant spreading form, combining watering with spraying to wash the leaf surface is also very beneficial. In winter, bonsai trees should not be fertilized, but 15 days before the beginning of winter, in combination with weeding and loosening the soil, killing pests and diseases, apply one fertilizer mainly of phosphorus and potassium, so as to strive for robust plant growth before winter and improve cold resistance.

2. Do not prune, eliminate pests and diseases

In winter, temperatures are low and growth vitality is low, so generally pruning is not suitable.

Pest control in winter can reduce pest and disease damage the following year. Before the beginning of winter, spray the entire tree once with equal-strength Bordeaux mixture to prevent diseases. If holes are found in the trunk, they may be plugged with medicated cotton, or coated with a mixture of mud, lime powder, and sulfur powder to achieve the effect of killing overwintering insect eggs. For the underground part (including the potting soil), a mixed dilution of dimethoate emulsifiable concentrate and dichlorvos can be used for irrigation to kill insects.

3. Maintain light, prevent cold and freezing

Different plants need different durations of light. For example, coniferous types such as pines and cypresses, evergreen small-leaf banyan, Japanese bush cherry, and Chinese privet need longer light duration, with 8 hours of light per day being ideal. For non-cold-tolerant plants such as Milan, lantana, and orange jasmine, when the temperature falls below 6°C, cover and protect them with plastic film, or move them to a sunny place.

Key Points for Stump Bonsai Care

1. Watering

Watering is one of the most important and most frequent measures in stump bonsai management. When a stump is planted in a pot, whether a deep pot or a shallow pot, the soil is always limited, and the water it contains is also limited. If water is not replenished by watering over a long period, the stump will wither from lack of water. Therefore, one should observe promptly and water according to the dryness or moisture of the soil to maintain soil moisture. Of course, watering must not be excessive either. If watering is excessive and the potting soil remains too wet for a long time, it can easily cause root oxygen deficiency and rot; at the same time, the amount of watering also depends on the specific tree species, seasonal changes, and whether the weather is cold or warm. Generally speaking, in summer or during drought, it is best to water once in the morning and once in the evening. In spring and autumn, water once a day or every other day. In spring when the stump begins to sprout, you may also water once in the morning and once in the evening as conditions warrant. During the plum rain season or on rainy days, watering is not needed, and attention should be paid to drainage. Sandy soil can be watered more, while clayey soil should be watered less. Watering can be done by spraying the leaf surface or by irrigating the roots. Generally the two are combined: first spray the leaf surface, then irrigate the roots thoroughly. Be careful not to give "half water," which causes the surface of the pot to be wet while the inside of the pot is dry. Also, leaf spraying should not be excessive, as it can easily cause leggy growth of branches and leaves.

2. Fertilizing

3. Prevention and Control of Pests and Diseases

Disease appearing on branches and trunk:

Manifested in rot of the phloem and cambium of branches and trunk, occurrence of stem rot and cankers on branches and trunk, rotting of the branch and trunk surface, decay of the inner wood, and spots appearing on twigs. Usually Bordeaux mixture should be sprayed, followed by lime sulfur mixture, and the rotted parts should be scraped away.

Leaf diseases:

Leaf diseases usually show symptoms such as yellow-brown or black spots, curled leaves, withering, and early leaf drop. They may be chlorosis, leaf spot disease, sooty mold, powdery mildew, and so on. For leaf spot disease, remove the diseased leaves and spray Bordeaux mixture; for chlorosis, spray the leaf surface with a 0.1-0.2 ferrous sulfate solution; for powdery mildew, spray with a 0.3-0.5 degree Beaume lime sulfur mixture.

Root diseases:

When the roots of a stump bonsai age, they are prone to various root rot diseases or root nodule diseases caused by bacteria and fungi. Attention should be paid to disinfecting the potting soil and controlling the amount of watering.

Scale insect control:

Scale insects are widespread and numerous in species. They are pests that suck the sap of the stump. After a stump is harmed by them, it is prone to sooty mold, showing poor growth, yellowing and withering of branches and leaves, and early leaf drop. Control methods, in addition to manually brushing them off and killing them, include spraying with a 1000-1500 times solution of 40% dimethoate emulsifiable concentrate, or a 1000-1500 times solution of 80% dichlorvos.

Red spider mite control:

Red spider mites harm leaves by sucking leaf sap. After infestation, the leaves take on a gray mottled color and are caused to wither, yellow, and drop. The control method is to spray with a 1500-2000 times solution of 40% dimethoate emulsion or a 1000 times solution of 50% phoxim wettable powder.

Aphid control:

Aphids are numerous in species and widespread in harm. Affected stumps generally have curled and drooping leaves, and in severe cases the leaf surface becomes dirty black, dry, and falls off. Control method: generally spray with a 2000-3000 times aqueous solution of 40% dimethoate, once a week. Or spray with a 2.5% rotenone 800-1200 times aqueous solution.

Pruning:

Bonsai trees are still constantly growing. If allowed to grow naturally without suppression, it will inevitably affect the tree's form and styling and cause it to lose its artistic value. Therefore, timely pruning is necessary: shorten long shoots, thin out dense shoots, so as to maintain a beautiful tree form and appropriate proportions.

Pinching:

For tree bonsai, in order to suppress its height growth and promote the development of side branches into a flat spread, the tender tips of the branch shoots may be pinched off.

Bud pinching:

When many adventitious buds grow at the base or on the trunk of a tree bonsai, the buds should be pinched off at any time to avoid the sprouting of forked branches that affect the beauty of the tree shape.

Leaf removal:

For foliage-appreciation tree bonsai, the ornamental period is often the period when new leaves sprout. For example, the new leaves of maple and pomegranate are red. Through leaf removal treatment, the tree can be made to sprout new leaves several times a year, bright and pleasing to the eye, improving its ornamental effect.

Branch pruning:

Tree bonsai often produces many new branches. To maintain its beautiful styling, attention must always be paid to pruning. The pruning method should be determined according to the tree form. For example, for a cloud-layer style, the branches should be pruned into a flat and even shape. Generally, dead branches, parallel branches, crossing branches, and others that detract from beauty should all be cut off promptly.

Root pruning:

When repotting, combine it with root pruning. Roots that are too dense or too long should be pruned. This can be considered according to the following situations. If the tree's new roots are poorly developed and the root system has not densely covered the bottom surface of the soil ball, then the original pot may still be used for repotting, and root pruning is not needed. For tree species with well-developed root systems, where the fibrous roots densely cover the bottom surface of the soil ball, a slightly larger pot should be used, the dense root system should be thinned, old roots removed, and a few new roots retained for repotting. For some old stump bonsai, when repotting, the roots may be appropriately raised to increase ornamental value. Also prune away old roots and portions of the root tips, and cultivate with loose, fertile soil to promote the growth of new roots.

Repotting and soil changing:

After a bonsai tree has grown in a pot for many years, fibrous roots densely fill the bottom of the pot, making it difficult for water to penetrate and drain, and fertilizer is also not easily absorbed, which will affect the normal growth of the tree. At this time, it should be repotted and the soil changed. For repotting, the original pot may be used or a pot one size larger may be chosen, determined according to the size of the tree. Changing the soil can improve soil aeration and water permeability, increase soil nutrients, help the bonsai tree grow robustly, and improve its ornamental effect.

Repotting of tree bonsai can be determined according to the following aspects:

Placement and Protection

How to Grow Stump Bonsai? A Detailed Guide to Daily Care and Management

Winter Care and Management of Stump Bonsai

Key Points for Stump Bonsai Care

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