1. Pruning is based on the principle of "training trees by trimming branches" to shape and transform the tree structure. The first step involves removing overlapping, crowded, or intersecting branches, leaving those that are well-spaced and balanced without interfering with each other. To promote fruit production and restore tree vitality, some large branches are removed gradually over several years. In the first year, 1–3 major branches are cut back, while the rest are shortened to control their growth and temporarily retain existing fruits. This process continues in the following years to refine the tree's structure.
In the first year, weak and sparse branches are removed, and strong, branching shoots are selected for pruning. Long, non-flowering branches should be pruned as much as possible to make the canopy more compact and sturdy. On the outer edges of the tree crown, sparse shoots are thinned out, leaving fresh buds (red) to encourage new growth, concentrate nutrients, and improve fruit set.
In subsequent years, the balance between vegetative growth and fruiting is fine-tuned: 1) Remove dense, weak, or redundant branches, prune and renew them to keep the branches compact and promote healthy growth, leading to strong vegetative branches. 2) Lightly trim vigorous branches to slow their growth and encourage the development of robust fruiting branches. 3) Appropriately shorten long fruit-bearing branches to increase fruit set and ensure high-quality fruits. These practices not only support overall tree growth but also help maintain a sufficient number of fruiting branches, ensuring high yield and quality every season.
2. Bark scraping is done in early spring (March or early April), where the old, cracked bark on the trunk and large branches is scraped off and burned. This helps eliminate pests like Pyrosphaeridae, leaf curl insects, star caterpillars, and red spiders that may be hiding in old bark. After the first scraping, it should be repeated every 1–2 years to allow latent buds to develop into new shoots, helping renew the canopy or cultivate new fruiting branches. Continuous scraping can damage buds and prevent new growth.
3. Tree tray shaving is performed annually, during the spring budding and summer periods. One to three shavings are done to loosen the soil, remove root defects, and improve soil aeration, moisture, and nutrient levels. Combined with soil cultivation, water conservation projects are implemented, and tree trays are built to store water near the base.
4. Fertilizing before flowering takes place 15–20 days prior to blooming. Radial groove fertilization is used, starting with 2 kg of ammonium bicarbonate for two-year-old trees, and about 4.5 kg of chemical fertilizer annually (1 kg ammonium bicarbonate mixed with 3.5 kg ammonium superphosphate).
5. Spraying gibberellin during flowering helps preserve fruits. At the end of May and early June, 1 gram of refined Shanghai-made gibberellin is dissolved in 5–10 grams of alcohol and diluted in 20 liters of water, or 50 ppm of gibberellic acid is sprayed onto the canopy.
6. Top-dressing the roots from late June to August is done 3–5 times. A 0.3–0.5% urea solution is sprayed every 10–15 days, and in August, 0.3% potassium dihydrogen phosphate is applied once or twice.
7. Green manure pressing is carried out during the rainy season or from July to August. Furrows 0.5 meters deep and wide are dug under the tree canopy, and wild weeds are pressed into the soil. Layers of grass are buried, and the soil is slightly raised above ground level. Each tree receives 50–100 kg of green manure.
8. Timely treatment of pests and diseases is essential to maintain tree health and productivity. White Pepper,Strong Aroma White Pepper,Herbs Flavoured White Pepper,Bell Pepper Granules White Pepper Sichuan Liuhang Agriculture Co.Ltd , https://www.lhagriculture.com
Hawthorn's pruning features and problems