How to plant ginkgo trees? A detailed explanation of cultivation points and management methods
How to cultivate ginkgo trees? The ginkgo tree is one of the street tree varieties with beautiful form; it not only has strong disease resistance but also high pollution tolerance. As one of the courtyard landscape trees, the ginkgo tree is extremely ornamental. Let's learn together the cultivation points and management methods of the ginkgo tree below.
1 Key points of ginkgo tree cultivation techniques
1.1 Seedling selection
To grow a healthy ginkgo tree, you must first select superior seedlings. Generally, ginkgo seedlings with relatively well-developed root systems should be chosen. Usually, ginkgo seedlings whose xylem is whitish and whose root bark is red are relatively healthy; if the root system is black or has turned black, it indicates that the seedling is already dead. If the ginkgo tree is to be used as a street tree, seedlings grown from seed and male plants should be chosen, and ginkgo seedlings with relatively straight trunks and trunk branching at about 3 m should be selected.
1.2 Planting
Before planting, relatively fertile soil should be chosen, usually soil with an organic matter content of 1%-3% and good water permeability is best. For ginkgo trees, planting before bud break in early spring makes it easier to survive, because early spring temperatures are neither high nor very low, providing natural conditions for the growth of ginkgo trees. Ginkgo trees are usually planted with a soil ball, but deep burial in the soil makes rooting difficult, so shallow planting is more suitable; the planting depth is generally best when it is 1-2 cm higher than the original root collar line and ground level of the seedling.
1.3 Watering
In the early stage of ginkgo cultivation, water once every 5-7 d; after the ginkgo tree survives, there is no need to water frequently. Usually the first watering is done after the soil thaws and before bud break, and the second watering is done when the weather is relatively dry. Although ginkgo trees are not afraid of drought, they are afraid of moisture. If there is too much water, it will invade the ginkgo root system, causing water accumulation at the roots, and in severe cases may lead to root death. However, among all ginkgo trees, cases of false death are unavoidable. That is to say, after some ginkgo trees are waterlogged, even if the roots die, the leaves will still unfold, and they will still sprout in early spring of the second year, but the leaves will become very small. After the nutrients in the ginkgo tree's body are exhausted, it will no longer sprout; this is the false death phenomenon of ginkgo trees. It should be noted that some ginkgo trees will not sprout in the first year of cultivation; do not assume that the ginkgo tree has died, as it is only very similar to the false death phenomenon and will not sprout until the second or third year. This is a manifestation of slow growth in ginkgo trees and is a normal phenomenon.
1.4 Pruning, intertillage and pest and disease prevention
First, before transplanting, the ginkgo tree can be pruned for trunk formation, and at the same time some overly dense branches and leaves as well as diseased and pest-infested branches and leaves should be cut off; during the growth process of the ginkgo tree, there is no need to prune again. Second, during maintenance, intertillage should be carried out in a timely manner to avoid the growth of weeds, which is beneficial to tree growth. At the same time, it improves soil aeration conditions, promotes root growth, and quickly sprouts new branches. Finally, compared with other trees, ginkgo trees have very few pests and diseases; only when summer temperatures are relatively high are the stems more prone to invasion by pests and diseases, and rot disease is likely to occur after rain. Therefore, in summer a shade shed can be built for ginkgo trees to prevent pests and diseases.
2 Ginkgo tree management techniques
2.1 Training and pruning
Training and pruning ginkgo trees can promote their rapid growth and development. Therefore, root sprouts and some diseased plants should be cut off regularly every year so that nutrients are concentrated in the main trunk and main branches, keeping the ginkgo tree in good tree form, ensuring the tree is tall and the branches are straight, and thereby enabling the ginkgo tree to present a more beautiful landscape effect as a street tree.
2.2 Artificial pollination
Ginkgo trees are wind-pollinated plants, so artificial pollination is needed. The simplest artificial pollination method is to cut off male flower branches that are about to bloom from other trees and hang them high in the windward position. Another method is artificial liquid pollination: after picking fresh male flowers, add water, filter out the residue, then add 1% sucrose and 0.2% borax to the pollen for artificial liquid pollination. The best time for artificial pollination is generally chosen when a small round bead appears on the stigma of the female flower; when the flowering period encounters adverse weather such as rain and fog, artificial supplementary pollination is generally used as a remedy.
2.3 Fertilization management
Ginkgo trees grow slowly, and strengthening fertilization management can accelerate their growth. Usually, in addition to appropriately increasing base fertilizer according to the growth condition of the ginkgo tree, topdressing should be done once or twice before bud break to promote new shoot growth, generally applying 0.8-1.0 kg of compound fertilizer per plant.
3 Pest and disease control
During the growth process of ginkgo trees, the most common diseases are leaf blight and stem rot, both of which are fungal diseases. For the control of leaf blight, in the early stage of seedling growth use 25% carbendazim 500-fold solution and 70% thiophanate-methyl 600-fold solution to spray evenly two or three times, and promptly remove fallen leaves. For stem rot, spray the whole tree with Liangguoan 800-fold solution. For ginkgo trees that suffer from stem rot every year, Virus No. 2 300-400-fold solution should be diluted and then sprayed over the whole plant and used as a root drench.
The most common ginkgo tree pests are leaf roller moths and thrips. For leaf roller moths, the pest bags and rolled leaves can be removed manually to control the damage, and 50% phoxim emulsifiable concentrate 1000-fold solution can also be sprayed to trap and kill adults. For thrips, in the early stage of ginkgo tree growth, spray 2.5% deltamethrin emulsifiable concentrate 2000-fold solution or spray 40% dimethoate or omethoate emulsifiable concentrate 1000-1500-fold solution for control.
The above are the key points of ginkgo tree cultivation techniques. Seedling growers interested in the ginkgo variety can take a good look. It is suggested that those who have not downloaded the Huinong mobile APP download one, so they can learn anytime and anywhere every day!
Introduction to ginkgo tree planting techniques and cultivation management points
The ginkgo tree is an excellent tree species for both fruit and timber, with a tall and beautiful tree form, and it is also a beautiful ornamental tree species. Ginkgo has strong adaptability to soil, is tolerant of acid, alkali and drought, and has a lifespan of several hundred years, even more than a thousand years; people call it the "grandfather-grandson tree." The fruit is rich in ginkgoic acid and ginkgol, is nutritious, can be eaten, and can also be used as medicine. The leaves can be used to make medicines such as "guanxintong," and can also be used as paddy field fertilizer and insecticide. Its wood is light, soft and tough, with fine texture, and is not easy to warp or crack, making it a good material for construction, crafts and furniture.
Planting value
Ginkgo is commonly known as white fruit tree, grandfather-grandson tree or duck-foot tree; after the late Quaternary glaciation it survived only in China and is one of China's important specialty fruit trees. The comprehensive utilization value of the ginkgo tree is very great. Its usable part is the seed kernel, which is nutritious, fragrant and glutinous and tasty, is a high-grade tonic and a good ingredient for high-grade dishes, and also has certain medical value, with effects such as resolving phlegm, relieving cough, tonifying the lungs, treating dysmenorrhea, stopping turbidity, promoting diuresis and sterilizing.
The ginkgo tree posture is upright and majestic, the leaf surface is clean and elegant, it has a certain resistance to smoke and dust pollution, and it can purify the air. It has very few pests and diseases, so it is also an important landscape tree and an excellent tree species for greening around the four sides. It is also used to make stump bonsai.
Ginkgo wood is fine and soft, elastic, and not easily deformed; it is a material for fine crafts and precious household goods, but it takes too long to mature and production is relatively small. The leaves can be used to extract the new drug guanxintong for treating diseases of the vascular system; even fallen leaves can be used for making medicinal pillows. The fleshy seed coat outside the nut can be used to extract tannin extract, and when mashed and mixed with water it can be made into a crude pesticide with insecticidal effect.
Main types
Ginkgo currently has only one genus and one species. In addition, there are variants such as leaf-bearing ginkgo, in which some seeds grow on the leaves and the seed stalks merge into one. In plant taxonomy, ginkgo belongs to the gymnosperms. The ovules are produced on the ovule-bearing receptacle, with no ovary covering outside, so the mature seeds do not have an outer fruit skin. The drupe-like "fruit" usually seen is actually the seed of ginkgo.
Cultivated varieties are usually divided into three categories according to the traits of the seed fruit and seed kernel: Foshou, Meihe and Mal-ing.
The seed kernels of Foshou-type varieties are mostly long obovate to elliptical, with ridge lines on both sides but no obvious wing edges. The seed kernel is plump and sweet-tasting.
The seed kernels of Meihe-type varieties are relatively small, often nearly round, slightly flattened, and often uneven in thickness on the dorsal and ventral surfaces; the ridge lines on both sides form an elliptical or spindle shape not far from the base, with ridges on the sides but inconspicuous wings.
The seed kernels of Mal-ing-type varieties are elliptical or spindle-shaped, with ridges on the sides but inconspicuous wings. Their form is intermediate between the Foshou type and the Meihe type.
Growth habits
Ginkgo is a deciduous fruit tree with slow growth, late bearing and a long lifespan, dioecious, and often forms a tall crown with strong trunk dominance and obvious layered rows. Seedling-grown trees mostly have tower-shaped, conical or oval crowns; grafted trees, when lacking a central trunk or when central trunk development is inhibited, can begin to form semicircular or open-center crowns in the later growth stage. Branches within the crown are clearly divided into two types: long branches and short shoots. Long branches are formed by several buds at the tips of branches extending upward and outward, and are the basis for forming the crown.
Short shoots are formed by buds in the middle and lower parts of branches first forming leaf cluster branches, and then weakly extending and accumulating each year, with extremely short internodes; they are also called "scale branches" or "milk branches." Under certain conditions, short shoots can also send out long branches. For young trees under 10 years old, the proportion of long branches sent out is relatively high, accounting for about 70% of the total number of branches produced. For large trees over 50 years old, the number of long branches sent out drops sharply, and the proportion of short shoots increases significantly, accounting for more than 80% of the total number of branches produced, so the crowns of mature large trees are often relatively sparse. Sometimes, latent buds on old trees or large branches can also directly sprout to form short shoots.
After reaching fruiting age, the female flowers and male inflorescences of ginkgo trees are respectively clustered on the short shoots of female and male plants. Short shoots have 5 to 14 leaves, varying; generally, robust short branches with 6 or more leaves can form flower buds. The flower buds are mixed buds, terminal, and after sending out extremely short shoots in spring, they bloom in the leaf axils. Each short shoot on a female plant can bear 2-14 seeds (generally 5-6). Whether flower buds can form on short shoots is related to the nutritional status of the tree body and the branch age and growth condition of the base branch on which the short shoot is borne. Generally, on base branches 3-12 years old, short shoots bear the most fruit, and afterward the fruiting ability gradually declines.
The sprouting rate of long branches in ginkgo is extremely high. Apart from the several buds at the tip sending out long branches, the axillary buds on all the other nodes can send out short branches and form flower buds that bloom and bear fruit, thereby very easily forming alternate bearing. However, short shoots on the same base branch sometimes show alternating fruiting. The axils of short shoots on male plants bear male inflorescences, with 4-6 borne on each short shoot.
Propagation methods
The propagation methods of ginkgo trees include seedling propagation, division and grafting, among others; what is widely used in production is division and grafting. Seedling propagation bears fruit late, and the seed kernels produced are small; it is mostly used to cultivate trees for both timber and fruit, or to cultivate rootstock seedlings. Seeds can be sown in winter or sown in spring after sand storage; about 600 kg-750 kg of seed kernels are needed per thousand sq m of seedbed. When ginkgo emerges, the cotyledons do not come out of the soil, so the soil covering can be appropriately thicker. Seedlings grow quite slowly, and shading is suitable during high summer temperatures. One-year-old seedlings have underdeveloped lateral roots, and seedling height is no more than 20-30 cm. They are not suitable for leaving the nursery or for grafting. Generally they need to be grown for 2-3 years after being moved to a different bed, and only when the seedling height reaches 60-100 cm can they leave the nursery.
Division makes use of the sprouts produced at the base of ginkgo plants, carried out before sprouting in spring during February-March. Carrying along part of the old roots and fibrous roots is beneficial for survival. The fruiting age of division-propagated seedlings is earlier than that of seedling-propagated seedlings, but it still takes about 10 years. After division-propagated seedlings are cultivated, they can be directly planted in the field, or they can be used as rootstock for grafting afterward. When dividing, it is advisable to select more roots from female plants.
The survival rate of ginkgo cuttings is lower than that of generally easy-to-root tree species, but propagation by cuttings can save seeds and expand the seedling source. Cutting methods are divided into hardwood cuttings and greenwood cuttings. For hardwood cuttings, select one-year-old branches as cuttings, cut them to about 20 cm, cut the lower end into a horse-ear shape, treat with 30 ppm to 50 ppm naphthaleneacetic acid solution (the active ingredient of rooting agent) for 12-24 hours, or soak with 50 ppm ABT-1 rooting powder for 1 hour, then insert the cuttings, with a planting depth of about 10 cm.
Ginkgo trees propagated by grafting bear fruit the earliest, and the tree body is relatively short, making management convenient. In the past, production areas mostly used large rootstock and high-trunk grafting, which was not conducive to large-scale rapid seedling cultivation and orchard establishment. At present, production mostly promotes low seedling grafting, that is, using 2-3-year-old rootstock seedlings and grafting at a relatively low position 30 cm-50 cm from the ground, with one-year-old branches used as scions. The specific grafting methods mainly include cleft grafting and bark grafting. The grafting period is from mid-to-late March to early April.
Planting and management
For ginkgo orchards planted in blocks, open land with deep soil layers and good drainage should be chosen; low-lying damp places, places with heavy salinity and alkalinity, and places with heavy clay soil are all unsuitable for orchard establishment. Planting distance can generally be 4 m-5 m between plants and rows; if planned close planting is implemented, the spacing between plants and rows can be further reduced. Ginkgo leaf-harvesting orchards that are established use highly dense planting, with spacing between plants and rows of only 0.7-1 m. Ginkgo trees scattered around the four sides mostly can form large crowns, so the spacing between plants and rows can be expanded to 6-8 m. Ginkgo roots recover slowly after being injured; the larger the sapling, the longer the recovery time. When planting and moving seedlings, the root system should be injured as little as possible, so as not to prolong the recovery period and affect growth and fruiting.
Ginkgo trees grow slowly, and strengthening soil and fertilizer management can accelerate growth. In addition to appropriately increasing base fertilizer according to the growth condition of the tree body, topdress 1-2 times before bud break to promote new shoot growth, applying 0.8 kg-1 kg of compound fertilizer per plant or watering with decomposed human manure and urine. Ginkgo avoids waterlogging, and during the rainy season attention should be paid to ground drainage.
Pests and diseases and their control
There are not many pests and diseases harming ginkgo; the main ones are leaf blight and stem rot, both fungal diseases. For leaf blight, 25% carbendazim 500-fold solution or 70% thiophanate-methyl 600-fold solution can be sprayed 2-3 times during the growth period, and fallen leaves should be promptly swept up and burned. For stem rot, 25% carbendazim 500-fold solution or 70% thiophanate-methyl 600-fold solution and 240-fold Bordeaux mixture can be used alternately 2-3 times during the growth period.
The main pests include longhorn beetles, bagworms, thrips and the ginkgo minute leaf roller. Thrips harm young tender ginkgo leaves; in the early growth stage, spray 2.5% deltamethrin emulsifiable concentrate 2000-fold solution or 20% fenvalerate emulsifiable concentrate 3000-fold solution, and 40% dimethoate or omethoate emulsifiable concentrate 1000-1500-fold solution can also be used for control. The larvae of the minute leaf roller web leaves and bore into short shoots in early summer; the pest bags and rolled leaves can be removed manually, sugar-vinegar jars can be hung during the adult emergence period to trap and kill them, or 50% phoxim emulsifiable concentrate 1000-fold solution can be sprayed for control.
Ginkgo bonsai production methods and cultivation and care points
Ginkgo is a famous long-lived tree species with strong vitality and unusual leaf shape; it is easy to propagate by grafting and to train and prune, and is a high-quality material for making bonsai. Ginkgo bonsai made from ginkgo tree milk is even more superb, with very high ornamental value and economic value. Ginkgo is a commonly used tree species in Chinese bonsai; ginkgo bonsai have thick trunks, curved branches, exposed roots, unique shapes, vigorous and unrestrained elegance, and are full of interest, making them a unique excellence among Chinese bonsai.
Pot soil preparation:
Because potted ginkgo is limited by the container, root growth is inhibited, and the limited pot soil must contain sufficient fertility to maintain the needs of ginkgo growth and fruiting. Select loose, fertile garden soil and sieve it, add one third fully decomposed organic fertilizer (such as compost, barnyard manure, green manure, etc.), mix in one fifth crushed plant straw, wet the above materials with 5% human manure and urine or 1% urea water solution, with moisture content such that it forms a ball when held in the hand and disperses when the hand is released, place it in a sunny place for piling, cover it tightly with plastic film, and ferment at high temperature for 15 to 25 days.
Container selection:
Choose different containers according to different placement locations. For viewing placed on a desk or windowsill, choose a ceramic or earthenware flowerpot with a diameter of about 30 cm, a height of 30 cm, and a drainage hole at the bottom; for viewing placed in a courtyard or on a balcony, containers such as wooden buckets, small boxes, small vats and flowerpots can be used. Change the pot once every 1 to 2 years, and at the same time fill in part of the new humus pot soil.
Careful planting:
After the soil thaws in spring and before the seedlings sprout, choose 2-year-old robust seedlings with well-developed lateral roots, no pests or diseases, and a basal stem of 1 cm to 2 cm, prune the root system, and cut the wounds smooth to facilitate wound healing. Before planting, soak the seedling and the new pot in water for a day and night. First place a small piece of tile over the drainage hole of the flowerpot so that it can drain water without leaking soil. Then fill half of the pot with soil, with the middle high and the surroundings low, spread out the seedling root system, keep the root trunk upright, fill with soil, gently lift the seedling by hand and then shake the pot to let the soil settle, then fill with soil and press firmly. The pot soil should be 3 cm to 5 cm below the pot rim so that sufficient water can be poured. Be careful to prevent pouring half water, with the top wet and the bottom dry, which affects survival and growth. Water thoroughly and place in a cool place for recovery.
Grafting for seedling propagation:
Choose superior early-fruiting and high-yielding varieties for grafting; after surviving for three years they can bear fruit. Relatively superior varieties include Tancheng No. 3, Dafozhi, Dongting Huang and others. Before bud break in spring, use the cleft grafting method, or from July to August use budding with wood, spring grafting sprouts in the same year, and autumn grafting survives in the same year and sprouts in the second year after the rootstock is cut.
Pruning and shaping:
According to individual appreciation level and aesthetic viewpoint, train it into a suitable tree shape. Such as bow shape, two-layer flat-spreading type, cross shape, spindle shape, etc. For the bow shape, use iron wire 2 cm to 4 cm in diameter to bend into a bow shape, fix it on the pot in the spring of the second year, and tie the new branches along the tree shape; finishing the shaping takes 3 to 4 years. The latter three tree shapes can be achieved through measures such as propping, pulling and bending to fix the branches in the expected positions, carrying out shaping and pruning year by year; in the third year, select a strong branch on the sunny side of the upper crown and graft a male branch for pollination.
Fertilizer and water management:
Bonsai cultivation is affected by container size and soil fertility, and water in the pot evaporates relatively quickly, so observe frequently and water in a timely manner. Watering should depend on the pot soil and leaves to decide the number of waterings, generally once every 1 to 2 days. In hot and dry seasons, water the roots once before 8 a.m. and once after 5 p.m. each day, and also spray the leaf surface to wash off dust on the leaves, which is beneficial to photosynthesis, increases local humidity, and meets the physiological needs of ginkgo. After leaf fall in autumn, take out the surface soil in the pot and replace it with loose, fertile nutrient soil, then water to settle it. When sprouting in early spring, apply sprout-promoting fertilizer mainly of nitrogen fertilizer; at full flowering stage, spray 0.1% borax solution; after flowering, during the fruit enlargement stage, apply fertilizer mainly of phosphorus and potassium fertilizer. Fertilization for potted ginkgo should be applied less but frequently, which can both prevent root burn and allow full absorption.
Pest and disease control:
The main ginkgo pests include slug moths and the minute leaf roller, among others, and the main diseases include root rot and leaf blight. Root disease is generally caused by water accumulation at the roots; leaf blight is mainly caused by lack of fertilizer and weakened tree vigor, and is also related to high temperatures. According to different pests and diseases, correct control measures should be taken. Strengthening fertilizer and water management, enhancing tree vigor and improving tree resistance are also effective ways to prevent and control pests and diseases.