Detailed Explanation of Early-Fruiting Cultivation Techniques for American Black and Red Globe Grapes
I. Orchard Establishment Techniques: 1. Site selection: Grapes are best suited to loose, sandy loam soil rich in organic matter. 2. Trellis selection: To achieve earlier fruiting and increase early-stage yields, a trellis system should be chosen, mainly the single hedge trellis. Row spacing 2-2.5 m, trellis height 2-2.5 m, post spacing 4-5 m, on the posts at 50 cm above ground and then every 40-50 cm upward, stretch one wire each, for a total of 4 wires.
I. Orchard Establishment Techniques:
1. Site selection: Grapes are best suited to loose, sandy loam soil rich in organic matter.
2. Trellis selection: To achieve earlier fruiting and increase early-stage yields, a trellis system should be chosen, mainly the single hedge trellis. Row spacing 2-2.5 m, trellis height 2-2.5 m, post spacing 4-5 m, on the posts at 50 cm above ground and then every 40-50 cm upward, stretch one wire each, for a total of 4 wires.
3. Planting density: Row spacing 2 m, plant spacing 1.5 m, 330 plants per mu, training with 3-5 canes.
4. Planting techniques:
(1) Digging high-yield trenches: Before planting, first dig high-yield trenches 50 cm wide and 60 cm deep; before backfilling, fill the trenches with organic fertilizer or straw, etc.
(2) Planting time: The best time to transplant nutrition-bag seedlings is early June; hardwood cutting seedlings are planted in late November.
(3) Planting requirements: First mark the planting points according to the spacing requirements, then dig planting holes 30-40 cm square for planting. For nutrition-bag seedlings, select strong seedlings 20-30 cm tall with thick stems and thick, large leaves; the survival rate can reach over 95%. For one-year-old hardwood cutting seedlings, select first-grade seedlings with fibrous roots and 3-4 plump buds for planting. When planting, firm the soil as you backfill, water immediately after planting, then cover with a small mound of soil.
(4) Mulching with plastic film: The following year, dig out the soil to release the seedlings, water with yang water, and promptly cover with plastic film, which helps raise temperature and conserve moisture, promotes recovery from transplanting, and encourages early new shoot growth.
II. Vine Management:
1. Soil, fertilizer, and water management:
(1) Soil management: Based on weed occurrence, cultivate and weed 3-5 times throughout the year; combined with autumn fertilization, deep-turn the entire orchard once to a depth of 20 cm, which will help loosen the soil and promote root growth.
(2) Fertilization: Grapes like fertile and loose soil. Applying more organic fertilizer can effectively increase soil nutrients and improve soil structure; this is an important foundation for high quality and high yield. First, base fertilizer: autumn base fertilizer should be applied early and in sufficient quantity; after fruit harvest, deep-turn the soil 20 cm and apply 4000-5000 kg of organic fertilizer per mu, mixed with phosphate fertilizer or compound fertilizer. Second, bud-promoting fertilizer: before bud break, apply in furrows, 10-15 kg of urea per mu. Third, fruit-promoting fertilizer: after fruit set, when berries are bean-sized, apply mainly nitrogen and phosphorus, 15 kg each of urea and compound fertilizer per mu. Fourth, fruit coloring fertilizer: mainly potassium and phosphorus, 10 kg of compound fertilizer per mu. Fifth, foliar topdressing: during the growing season, spray 0.3% monopotassium phosphate plus trace element fertilizer on the leaves.
2. Training and pruning: No trunk, regular fan shape; select and retain 3-4 vigorous new shoots to train 3-5 main canes to form a fan shape. In the second year, on the main canes, every 20-25 cm, select and retain one fruiting branch group.
3. Summer pruning:
(1) Bud rubbing and branch thinning: To reduce nutrient consumption, bud rubbing should be done early rather than late. Black Big Pearl and Red Globe both have relatively high bud break, so excess branches should be rubbed off early; among double or triple buds, keep only the main bud, and retain one vigorous bud per node.
(2) New shoot pinching and lateral shoot treatment: Pinching of fruiting shoots is generally done one week before flowering. For lateral shoot treatment, the topmost lateral shoots above the inflorescence should retain 3-4 leaves and be repeatedly pinched.
(3) Cluster tip pinching and cluster shaping: Black Big Pearl and Red Globe both have the characteristics of large clusters and large berries. Only trimmed inflorescences can achieve large berries and attractive cluster shape. The method is: during the rapid elongation period of the inflorescence before flowering, about one week before flowering, pinch off the tip portion of the inflorescence by hand, accounting for 1/5-1/3 of the inflorescence length; at the same time remove secondary clusters and pinch off about 1/2 of the first and second branches of the inflorescence, so that the inflorescence forms a short cylindrical shape, which helps increase fruit set rate, increase berry weight, make the cluster a compact conical shape, and improve commercial appearance quality.
(4) Tying, pruning, and leaf removal to improve ventilation and light conditions: When grapes grow to July-August, branches and leaves are lush and can easily cause shading; treatment should be done early. Tying new shoots is routine work and should be carried out 3-4 times each year. When new shoots grow too vigorously and there are too many branches and leaves, affecting ventilation and light penetration, prune the shoots promptly, cutting off the tip portion of overly long branches, and thin out weak branches and old leaves to improve ventilation and light conditions.
4. Winter pruning:
(1) Pruning length of fruiting mother canes: Black Big Pearl and Red Globe grapes have relatively high fruitfulness of buds at the base of fruiting mother canes, so medium and short cane pruning is used. In production, hedge trellis cultivation should mainly use medium-long canes, combined with short cane pruning.
(2) Branch group renewal: To prevent the fruiting position from moving outward and to ensure vigorous fruiting mother canes every year, the double-branch renewal method should be chosen. Through pruning of renewal spurs each year, the outward movement of the fruiting position can be effectively controlled.
III. Disease Control:
1. Agricultural control: Strengthen summer pruning, improve ventilation conditions on the trellis surface, and promptly prune diseased leaves, diseased branches, and diseased fruit for centralized burning.
2. Chemical control: During the growing season, spray 1:0.5:200 Bordeaux mixture to prevent downy mildew; during the disease period, spray 25% metalaxyl 600 times solution, or Daconil 600 times solution.