A Detailed Guide to High-Efficiency Cultivation Techniques and Routine Care Management of Ginkgo

How is ginkgo cultivated? Ginkgo is a large deciduous tree with slow growth and an extremely long lifespan. It combines ornamental, medicinal and economic value, making it an excellent tree species. Below we mainly study ginkgo cultivation techniques and post-planting management.

1 Ginkgo Cultivation Techniques

1.1 Site Selection

Planting should be carried out on gently sloping land at an altitude of 170 m with good light conditions, deep and fertile soil, and good irrigation conditions. The best choice is leeward, sunny or gently sloping land with a soil pH of 6.5-7.5 and a slope of less than 15 degrees, or flat land with convenient transportation and close to a water source.

1.2 Selecting Superior Varieties

The selection of superior varieties is the foundation for cultivating strong seedlings; choose robust plants with strong resistance and no pest or disease damage. Seed collection is carried out from the end of September to early October, when the seeds are fully mature. Then remove the seed coat, wash clean, dry in the shade, and select plump, well-filled seeds for immediate sand storage. The best sand moisture level is one at which the sand forms a ball when squeezed by hand and falls apart when released. In addition, during storage, attention should be paid to drainage and rat prevention.

1.3 Sowing at the Right Time

After seed collection, remove the outer coat, dry in the sun and store. Sow in winter of the same year or in spring of the following year (if sowing in spring, carry out germination promotion treatment first). The nursery should be chosen on a plot with convenient drainage and irrigation, sufficient water, and relatively high terrain, and sufficient base fertilizer should be applied, with a seeding rate of about 25 kg/667 sq m. Before sowing in furrows, water the bottom thoroughly first, then place ginkgo seeds sideways in the sowing furrow. If the seeds have already germinated, place the sprout tip downward, cover with about 3 cm of fine soil and press firm. Ginkgo grows very slowly and requires two to three years before it can leave the nursery; when it leaves the nursery, the ginkgo seedling height is 60-70 cm.

1.4 Planting Method

In spring, plant about 15-20 days before bud break, while in autumn plant in mid-October. The best planting depth is to maintain the original soil mark of the seedling; it may be shallow, but it absolutely must not be too deep.

2 Management After Planting Ginkgo

2.1 Water and Fertilizer Management

Water the ginkgo saplings 5-7 d after cultivation. After the ginkgo saplings survive, the watering frequency can be reduced. Carry out the first watering after the soil thaws and before the ginkgo saplings bud. Carry out the second watering in May when the weather is dry, which is extremely beneficial to the growth and development of ginkgo buds. Because ginkgo is afraid of waterlogging and tolerant of drought, during the rainy season the amount of watering should be reduced according to weather conditions, and attention should be paid to drainage work, so as to avoid excessive water causing oxygen deficiency in the ginkgo root system and leading to root rot. The best fertilization time is spring and autumn. Ring fertilization can be carried out outside the projection of the tree canopy, or the hole-punching method can be used to apply organic fertilizer around the ginkgo tree and water it.

2.2 Shaping and Pruning

Ginkgo is a natural spur-type fruit tree; spurs are easy to cultivate and renew, and second-year spurs on long branches can flower and bear fruit. Therefore, the natural open-center shape is the main high-yield tree form for ginkgo. There is no central trunk; cultivate three or four main branches from the grafted part, cultivate 2-4 lateral branches on each main branch, grow long branches from the lateral branches, and cultivate fruiting spurs from the growing branches, with the canopy forming a hemispherical or natural open-center shape. For the shaping and pruning of young trees, keep the first branch at a length of 40 cm, keep the second branch at a length of 30 cm, and finally form the third branch. Subsequent pruning consists of cutting off the tender tips of new branches growing toward the side of the biased crown, removing sprouts and suckers, and cutting off weak twigs, upright branches, water sprouts, diseased and pest-infested branches, and overly dense branches; use rope to pull apart overly dense strong branches to ensure moderate density and good ventilation and light penetration, gradually developing them into a trunk-layered shape or a sparse open-center shape. The shaping and pruning of fruiting trees is the same as the shaping and pruning method for young trees after they form the third branch.

2.3 Artificial Pollination

Fruiting orchards should carry out artificial pollination. In late April, when the flowering rate of female flowers exceeds 40%, collect male flower pollen, and mix pollen, boric acid and water in a ratio of 1:0.25:(250-500) and spray.

2.4 Artificial Fruit Thinning

In order to effectively overcome the phenomenon of alternate bearing and ensure a robust tree vigor, reasonable fruit thinning should be carried out. According to the tree's growth vigor, spurs with more than 6 leaves keep 3 fruits, those with four or five leaves keep 2 fruits, and those with three or four leaves keep 1 fruit. When thinning fruit, keep the large fruits and remove the small ones.

3 Pest and Disease Control

3.1 Ginkgo Leaf Blight

Strengthen water and fertilizer management to make ginkgo trees grow more robustly and improve their disease resistance. For example, before July, splashing zinc fertilizer or a mixed solution of trace elements such as zinc, manganese and boron (1:500) on the ground near the base of the ginkgo can effectively prevent this disease. In the early stage of the disease, spray young trees or seedlings with 70% mancozeb 800 times solution or 50% Tuzet 800-1,000 times solution or 25% carbendazim wettable powder 600-800 times solution for control; depending on the severity of the disease, spray once every 15-20 d, for two or three consecutive sprays.

3.2 Ginkgo Early Yellowing Disease

Zinc deficiency in the soil, water accumulation, underground pests or insufficient soil moisture can easily cause ginkgo trees to become infected with leaf blight and to shed leaves early. It generally occurs in mid-June, and yellowing increases in early July. When controlling it, identify the cause accurately and pay attention to draining accumulated water and irrigating during drought; if zinc is deficient, apply zinc fertilizer, multi-effect zinc or zinc sulfate, etc.

3.3 Ginkgo Leafroller Moth

It mainly harms ginkgo trees from mid-April to mid-June, with larval damage being the most serious. Newly emerged larvae bore into tender shoots after one or two days, or cause the damaged branch tips to die and young fruits to drop. Spraying can be done before the larvae have just hatched and have not yet bored into the branch tips, or when the larvae crawl out of the branch tips and roll the leaves, such as mixing dichlorvos (80%), trichlorfon (90%) and water in a ratio of 1:1:(800-1,000) and spraying, or spraying with 1,500-2,000 times decamethrin solution.

4 Timely Harvesting

In order to improve the quality of ginkgo seed kernels, harvest in early October when the fruit is fully mature. After the fruit is collected, carry out treatments such as piling, rubbing off the skin and drying, then collect the seeds.

The above are all the key points of ginkgo tree cultivation techniques. Fellow seedling growers can refer to and learn from them, and can also recommend them to more seedling growers around you who need them!

Ginkgo Bonsai Cultivation and Care Techniques

Preparation of Potting Soil

Because potted ginkgo is limited by the container, root growth is inhibited, and the limited potting soil must contain sufficient fertility to maintain the needs of ginkgo growth and fruiting. Select loose, fertile garden soil and sift it, add one third fully decomposed organic fertilizer (such as compost, barnyard manure, green manure, etc.), mix in one fifth crushed plant straw, and wet the above materials with 5% human manure and urine or 1% urea water solution; the moisture level is reached when it forms a ball in the hand and falls apart when released. Place in a sunny spot to pile up, cover 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 on a desk or windowsill, choose a ceramic or earthenware flower pot about 30 cm in diameter, 30 cm in height, with a drainage hole at the bottom. For viewing in a courtyard or on a balcony, containers such as wooden buckets, small boxes, small vats and flower pots can be used. Repot once every 1 to 2 years, and at the same time fill in part of the new humus potting soil.

Careful Planting

After the soil thaws in spring and before the seedlings bud, select 2-year-old robust seedlings with well-developed lateral roots, no pests or diseases, and a base stem of 1 cm to 2 cm. Prune the root system and cut the wounds smooth to facilitate wound healing. Before planting, soak the seedlings and the new pot in water for a whole day and night. First place a small piece of tile over the drainage hole of the flower pot? so that it both drains water and does not let soil leak out. Then fill half the pot with soil? with the middle high and the surroundings low, spread out the seedling root system, keep the root stem 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 firm. The potting soil should be 3 cm to 5 cm below the pot rim so that sufficient water can be poured. Be careful to prevent pouring only half the water, leaving 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: Select superior varieties with early fruiting and high yield for grafting; after surviving for three years they can bear fruit. Relatively superior varieties include Tancheng No. 3, Dafozhi and Dongting Huang. Before spring bud break, use the cleft grafting method, or from July to August use bud grafting with wood; spring grafting sprouts in the same year, and autumn grafting survives in the same year and sprouts after cutting the rootstock in the second year.

Pruning and Shaping

According to individual appreciation level and aesthetic viewpoint, cultivate a suitable tree shape. For example, bow shape, two-tier spreading type, cross shape, spindle shape, etc. For the bow shape, bend iron wire 2 cm to 4 cm in diameter 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, completing the shaping in 3 to 4 years. The latter three tree shapes can be fixed in the expected positions by measures such as propping, pulling and bending, carrying out shaping and pruning year by year. In the third year, select a strong branch on the sunny side of the upper canopy and graft a male branch onto it for pollination purposes.

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 time. Watering should be based on the potting soil and leaves to decide the number of waterings, generally once every 1 to 2 days. In hot, dry weather seasons, carry out root watering once before 8 a.m. and once after 5 p.m. each day, and also spray water on the leaves to wash off dust from the leaf surface, which is good for photosynthesis, increases local humidity and meets the physiological needs of ginkgo. After leaf fall in autumn, take out the surface soil in the pot, replace it with loose and fertile nutrient soil, and water to settle it. When buds break 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 of potted ginkgo should be applied little but frequently, which both prevents root burn and allows full absorption.

Pest and Disease Control

The main ginkgo pests include slug moths and the leafroller moth, etc., and the main diseases include root rot and leaf blight. Root diseases are generally caused by water accumulation at the roots, while leaf blight is mainly caused by fertilizer deficiency and weakened tree vigor, and is also related to high temperatures. Correct control measures should be taken according to different pests and diseases. Strengthening fertilizer and water management, enhancing tree vigor? and improving tree resistance are also effective ways to control pests and diseases.

Ginkgo Bonsai Cultivation Techniques