The Latest Kiwi Fruit Planting Techniques and Methods Tutorial

Kiwi fruit belongs to the genus Actinidia in the family Actinidiaceae. It is a deciduous vine fruit tree, rich in various vitamins and nutrients, and is known as the “king of fruits”. It has high economic and cultivation value. It is suitable for planting in places with a mild climate, abundant rainfall, fertile soil, and lush vegetation, in black humus soil or sandy loam soil that is deep, well-drained, and moderately moist, with a pH value of 5.5-7, slightly acidic soil.

Selecting Suitable Varieties

Mainly Hongyang (red-fleshed fruit), Hayward, Bruno, Qingcheng No. 1, Qinmei, Miliang No. 1, Chuanmi No. 2, Chuanmi No. 3, Chuanmi No. 4, etc.

Seedling Propagation

1. Rootstock seedling cultivation

1.1. Seed collection. Collect fully mature fruits in early September to mid-to-late October. After they ripen and soften, squeeze the fruits out together with the seeds, put them into a gauze bag and rub them so that the seeds separate from the flesh, then rinse repeatedly with clean water, and spread the washed seeds indoors in the shade to dry.

1.2. Seeds. Sand storage treatment: soak the seeds in warm water at 40-50°C for 2 hours, then soak them in cold water for a day and a night, then store them in sand for 50-60 days before sowing. During sand storage, kiwi fruit seeds are afraid of drying out and of excessive moisture, so check and turn them frequently to prevent mold.

1.3. Sowing. ① Sowing time: generally, raising seedlings in areas above 800 m in altitude is relatively ideal, sowing from mid-March to early April. ② Sowing method: First, choose a nursery site in a place with deep, fertile soil and good drainage, irrigation, and transportation conditions; second, prepare the land and make beds, apply sufficient base fertilizer, remove debris, make the beds about 1 m wide, slightly compact the seedbed, water thoroughly, and sow the sand-stored seeds together with the sand. After sowing, spread a layer of fine river sand about 2-3 mm thick, cover with rice straw, spray water on the straw or build a small plastic tunnel. Third, strengthen seedbed management to ensure the cultivation of robust rootstock seedlings.

2. Grafted seedling cultivation

2.1. Grafting period. About 20 days before bud break is suitable, that is, from mid-February to late March.

2.2. Grafting method. Mainly adopt methods such as single-bud cut grafting. Specifically: select a scion that is plump in growth and has a relatively small pith, cut a branch segment with one bud, 3-4 cm long. Choose a flat side and peel off the bark layer, with the cut surface preferably 2-3 cm long, and the depth preferably exposing the xylem or slightly including the xylem, then cut a short slanted surface of about 50 degrees on the opposite side of the cut surface. Cut the rootstock at 10-15 cm above the ground, choose a smooth side and cut downward with one stroke, with the cut surface slightly longer than the scion cut surface and the same depth as the scion, peeling off 2/3 of the rootstock bark; then insert the scion, requiring the scion to be basically the same size as the rootstock; pay attention to aligning the cambium layers of the rootstock and scion, then wrap with plastic grafting film, exposing the scion bud eye.

2.3. Management of grafted seedlings. First, 3-4 weeks after grafting, the grafted bud begins to sprout; after the new shoot has basically aged, the binding film can be removed. Second, for side-grafted seedlings in spring and autumn, after they survive, cut the rootstock immediately, with the cut about 4 cm from the graft union. After summer grafted buds survive, the rootstock can first be bent and then cut. Third, promptly removing sprouts on the rootstock is the key to survival and shoot growth. Fourth, the nursery land should be frequently cultivated and weeded, taking care not to touch the newly emerged grafted buds during weeding. Fifth, after the grafted buds sprout and grow shoots, support stakes should be set beside the grafted buds, and the new shoots tied and protected on the stakes. Sixth, when seedlings are 60 cm tall, they should be appropriately pinched. Seventh, combined with irrigation, human excrement and urine, pig manure, etc. can be applied, or 1% urea can be added to the water; when fertilizing in July, an appropriate amount of superphosphate can be added to promote aging of the seedling branches and plump bud eyes. Eighth, from July to August, kiwi fruit seedlings should be shaded, avoiding direct strong light.

Orchard Establishment

1. Orchard site selection

The kiwi fruit root system is fleshy and especially fragile; it fears both waterlogging and high-temperature drought, and new shoots fear both being broken by strong wind and late spring cold or low-temperature freezing damage. It is suitable for planting in sub-alpine areas (800-1400 m in altitude). Choose a place with deep soil, fertile soil, loose texture, good drainage, and convenient transportation to establish the orchard. If cultivating kiwi fruit in low mountains, hills, or plains, appropriate drainage and irrigation facilities must be available to ensure no waterlogging in the rainy season and timely irrigation in the dry season. It is best to build a windbreak forest around the orchard.

2. Planting period

The best planting period in southern production areas is after kiwi fruit leaf fall and before kiwi fruit bud break in early spring of the following year, that is, from early December to mid-to-late February, and the earlier the better.

3. Arrangement of pollinator trees

Kiwi fruit is a dioecious fruit tree. The selection and arrangement of pollinating male plants is one of the conditions for ensuring normal fruiting. When selecting male plants, attention should be paid to the same flowering period as the main cultivar or slightly earlier, a large amount of pollen, and a long flowering period. The ratio of female to male plants is 6:1 or 5:1, giving high yield and good quality.

4. Planting density

Generally, planting density is closely related to the training trellis system. The density for the hedge trellis is 2 m × 4 m, the planting density for the T-shaped trellis is 3 m × 4 m, about 56 plants per mu, and the planting density for the flat-roof trellis is 3 m × 5 m.

5. Support establishment

Generally, supports are set up in the winter of the same year after planting, divided into posts (cement posts, wooden posts, stone posts, bamboo posts, and companion trees, etc.), crossbeams (cement posts, wooden posts, bamboo, and metal, etc.), and the trellis surface of iron wire, etc. According to local conditions, choose wooden trellises, steel trellises, concrete trellises, and companion tree trellises, etc. The main trellis types are the “Y” shaped trellis and the “T” shaped trellis.

6. Planting trellis types

There are 3 commonly used trellis types in kiwi fruit production, namely the hedge trellis, T-shaped trellis, and flat-roof trellis.

6.1. Hedge trellis. The post is 2.6 m long and 12 cm thick, buried 80 cm into the soil, with a clear height above ground of 1.8 m. On the trellis surface, 4 rust-proof iron wires are stretched from bottom to top, with the first wire 60 cm above the ground. Set one post every 8 m, and tie the branches and vines to the trellis wires. This trellis type is used relatively often in production.

6.2. T-shaped trellis. A horizontal crossbeam is set at the top of the upright post, forming a small T-shaped support. The total length of the post is 2.8 m, and the total length of the crossbeam is 1.5 m. Three high-strength rust-proof iron wires are stretched on the crossbeam. The post is buried 80 cm deep, with a clear height above ground of 2 m, and one post is set every 6 m.

6.3. Flat-roof trellis. The trellis height is 2 m, with posts set every 6 m, and the posts throughout the orchard can be arranged in a square. The total length of the post is 2.8 m, buried 80 cm into the soil. The posts around the trellis are connected with angle iron or steel bars, and grids are stretched between the posts with thick and thin iron wires to form a flat-roof trellis.

Cultivation and Management Techniques

1. Planting techniques

1.1. Preparation of planting holes. It is best to deep-plow the orchard land 60-80 cm in the previous autumn, determine the plant and row spacing according to 6 × 4 m or 4 × 4 m or 5 × 4 m, etc., and dig planting trenches or planting holes 60-80 cm deep and 80-100 cm wide. When backfilling topsoil into each hole, evenly mix in 50-100 kg of farmyard manure, 0.5 kg each of phosphorus, potassium, magnesium, and other chemical fertilizers, or add 1.5 kg of oil cake, and build a ridge or steamed-bun-shaped mound 20-30 cm above the ground.

1.2. Variety arrangement. Generally, in large orchards, female and male plants are evenly matched at 10-12:1; small orchards require more male plants, matched at a ratio of 8:1 or 6:1. The specific planting method is: in the middle row of every 3 rows, plant one male plant every 2 female plants.

1.3. Planting period and method. (1) Planting period: The planting period of kiwi fruit is the same as that of other deciduous fruit trees, and it can be planted in autumn and early spring. (2) Planting method: If a large amount of plant straw is buried in the planting hole, it should be allowed to settle before planting. When planting, place the seedling in the center of the planting hole, and do not let the root system directly contact fertilizer. Use your hands to spread the root system in all directions, cover the roots with fine soil, then cover and level the soil, tread slightly firmly with your feet, and water thoroughly to settle the roots. The planting depth should be such that the root crown is level with or slightly higher than the soil surface, and the graft union must not be buried in the soil.

2. Management techniques

2.1. Soil management. (1) Deep plowing and soil improvement: combined with applying base fertilizer, deep-plow and dig fertilizer trenches outside the root zone every year or every other year; within the tree canopy it should be shallow; after pruning and orchard cleaning are finished, deep-plow the soil outside the fertilizer trenches another 20-30 cm. (2) Cultivation and weeding: the cultivation depth should preferably be 10-15 cm. In spring, shallow cultivation near the tree plate; in summer from June to August, combined with weeding, carry out shallow cultivation, weeding, and loosening of the tree plate, so that the soil is loose and breathable and moisture retention and drought resistance are enhanced.

2.2. Fertilization management. First, base fertilizer: from late October to late November, immediately after fruit harvest, dig a ring-shaped trench 35 cm deep and 30 cm wide around the tree plate or open a trench along the plant row, apply decomposed organic fertilizer and add oil cake and phosphate fertilizer, then irrigate and cover with soil. Apply 1500-3000 kg of residue manure, 150-200 kg of oil cake, and 100-150 kg of phosphate fertilizer per mu. Second, topdressing before bud break: from late February to early March, apply quick-acting fertilizer mainly based on nitrogen fertilizer, and combine with irrigation, applying 6-10 kg of urea per mu. Third, fertilization during fruit expansion: one week after flower drop (late May to mid-June), apply 100-150 g of compound fertilizer and 6-10 kg of human and livestock manure water per plant. Fourth, fertilization in the late fruit growth stage: from late July to early August, apply fertilizer mainly based on quick-acting phosphorus and potassium, and control the application of nitrogen fertilizer to avoid excessive vegetative growth of branches; apply 200-250 g of phosphorus and potassium fertilizer per plant. Fifth, foliar topdressing: during full bloom and fruit set, use 0.3% potassium dihydrogen phosphate or 0.2% urea solution for foliar topdressing.

2.3. Water management. The kiwi fruit root system is distributed shallowly and is neither drought-tolerant nor waterlogging-tolerant; growth requires relatively high air humidity and maintaining sufficient soil moisture. First, before spring bud break, irrigate in combination with fertilization, 25-30 kg per plant, and depending on drought conditions, irrigate 2-3 times; second, during the summer drought period, irrigate 2-3 times depending on drought conditions; third, during the autumn rainy period, promptly open trenches in the orchard or between plant rows for drainage.

2.4. Training and pruning. (1) Training: training mainly uses tree forms such as hedge trellis horizontal training, few-main-vine free fan shape, and “T” shaped small trellis, mainly with light pruning and delayed bending, strengthening pruning during the growing season, and moderating vigor to promote flowering and fruiting. (2) Pruning ① Summer pruning: First, sprout removal, that is, removing sprouts emerging from the rootstock and vigorous shoots sprouting from the trunk or the base of the main vine; except those retained as reserve branches, all the rest are removed; second, pinching, that is, during fruit set, when spring shoots are already semi-lignified, pinch vigorous fruiting shoots at the 10th leaf or 7-8 leaves above the last fruit; pinch spring vegetative shoots at the 15th leaf; if secondary shoots sprout, they can be pinched leaving 3-4 leaves; third, shoot thinning, that is, removing summer shoots that are too dense or too long and affect fruit growth and the weak shoots among two new shoots sprouting from the same leaf axil; fourth, bending shoots, that is, in the young tree stage, bending, twisting, and pulling excessively vigorous new shoots to control excessive growth, and in early August lay the branches and vines flat to promote flower bud differentiation. ② Winter pruning: First, shoot thinning, mainly removing poorly developed vigorous shoots, overly dense branches, overlapping branches, crossing branches, diseased and insect-damaged branches, weak shortened branches, sprout branches with no useful value, and fruiting branches with no renewal capacity; the current-year robust vegetative shoots on fruiting mother branches are good fruiting mother branches for the next year; depending on growth vigor and cultivar characteristics, leave 8-12 buds and short-cut; leave fewer buds on weak branches and more buds on strong branches; extremely vigorous branches can be short-cut after the 15th node. Fruiting mother branches that have fruited for about 3 years can be retracted to a place at the base of the fruiting mother branch with strong branches and strong buds for renewal. Second, treatment of fruiting branches: fruited vigorous shoots are short-cut at 3-4 buds above the fruiting position; long and medium fruit branches can be short-cut leaving 2-3 buds above the fruiting position; short fruit branches are generally not pruned. ③ Branches retained as renewal branches are short-cut leaving 5-8 buds.

Pest and Disease Control

First, the main pests and diseases include flower rot, anthracnose, vine blight, brown spot, fruit soft rot, Phytophthora disease, root rot, and June beetle, clearwing moth, flower bud maggot, fruit-sucking noctuid, etc. Control is mainly by comprehensive control methods focusing on strengthening management, enhancing tree vigor, strengthening soil disinfection, and strengthening prevention. Second, fruit sunscald is mainly controlled by strengthening tree vigor management and reasonable pruning. During fruit growth and development (late August), bagging can prevent sunscald.

Harvesting and Storage of Kiwi Fruit

1. Harvesting. Generally, the soluble solids content of kiwi fruit is required to be above 6.2%. Early-maturing cultivars of Chinese gooseberry (Actinidia chinensis) are harvested from late August to early September, late-maturing cultivars from mid-to-late September to early October, and delicious kiwi fruit (Actinidia deliciosa) from late October to early-to-mid November, at the latest no later than frost. The best harvesting time each day is after the morning dew has dried and before noon; in the afternoon the temperature is high, and the fruit is prone to heating in the basket. After harvest, the fruit is generally graded and packed according to size specifications. Grade I fruit has a single fruit weight above 100 g; Grade II fruit of Chinese gooseberry is 80-100 g, and of delicious kiwi fruit 70-100 g; Grade III fruit is 50-80 g.

2. Ripening. After harvest, kiwi fruit undergoes a ripening process. The higher the ethylene concentration in the environment, the faster the ripening. Therefore, 1000 PPM ethephon can be used to soak the fruit for ripening, bringing it to market two weeks earlier. A polyethylene film 0.05 mm thick can also be used to seal up box after box of packed kiwi fruit in a whole stack, using the ethylene released by the fruit itself to promote ripening.

3. Storage and freshness preservation

3.1. Precooling. Methods such as forced-air cooling, cold storage cooling, or water cooling can be used to lower the temperature to, or slightly below, the storage temperature of 0-2°C. Fruit cooled with water must be dried promptly to eliminate moisture on the fruit surface.

3.2. Storage methods. Using methods such as room-temperature storage, low-temperature storage, and controlled-atmosphere storage, kiwi fruit can respectively undergo short-term storage (1-2 months), medium- and long-term storage (4-6 months), and long-term storage (6-8 months), among which low-temperature storage is the most widely used.

In commercial production, in order to soften the fruit and reach edible ripeness, the fruit is generally placed at 15-20°C and treated with ethylene at a concentration of 100-500 ml for 12-24 hours, then kept at 15-20°C for one week, after which it is ready to eat.