Fertilization Principles
In response to insufficient organic fertilizer inputs, poor soil fertility and water retention capacity, excessive fertilizer application in some tea gardens, imbalanced NPK ratios, severe soil acidification, and deficiencies in medium and micronutrients, the following fertilization principles are proposed:
1. Use a combination of organic and chemical fertilizers, partially replacing chemical fertilizers with organic ones, applying organic fertilizers in appropriate quantities and deep (below 15 cm).
2. Maintain a suitable nutrient ratio. Based on soil fertility conditions, types of tea, and yield levels, determine the nitrogen fertilizer application rate, enhance the use of phosphorus, potassium, and magnesium fertilizers, and pay attention to sulfur and boron supplementation.
3. For severely acidified soils (soil pH
4. Combine scientific fertilization with green cultivation techniques for increased production efficiency.
Fertilization Recommendations
1. Annual nitrogen (N) fertilizer application rates for bulk Green Tea and black tea production tea gardens: for yields below 200 kg/acre, apply 16–25 kg N/acre; for dry tea yields over 200 kg/acre, apply 22–30 kg N/acre. For high-quality green tea and black tea production tea gardens: apply 13–20 kg N/acre. For Oolong Tea production tea gardens: for yields below 200 kg/acre, apply 13–20 kg N/acre; for dry tea yields over 200 kg/acre, apply 18–26 kg N/acre.
2. Phosphorus (P2O5) at 4–6 kg/acre and potassium (K2O) at 4–8 kg/acre, with an appropriate NPK ratio of (4–5):1:(1–2); the recommended application rates include nutrients from organic fertilizers. In tea gardens with excessively high soil phosphorus and potassium content, reduce phosphorus and potassium fertilizer applications accordingly.
3. For magnesium-deficient, zinc-deficient, and boron-deficient tea gardens, apply magnesium fertilizer (MgO) at 2–3 kg/acre, zinc sulfate at 0.7–1 kg/acre, and borax at 1 kg/acre. For sulfur-deficient tea gardens, choose sulfur-containing fertilizers such as ammonium sulfate, potassium sulfate, magnesium sulfate, superphosphate, or potassium sulfate-based compound fertilizers.
4. Apply fertilizers in phases, with organic, phosphorus, potassium, and magnesium fertilizers mainly applied as base fertilizers, and nitrogen fertilizers divided between base and top-dressing applications.
5. Apply all organic, phosphorus, potassium, magnesium, and micronutrient fertilizers as base fertilizers. Apply 30%–40% of the annual nitrogen fertilizer as base fertilizer. The appropriate period for base fertilization is between late September and late October after the end of the tea season, combined with deep plowing at a depth of 15–20 cm.
6. Top-dress primarily with fast-acting nitrogen fertilizers. The timing of top-dressing depends on the growth and harvesting status of the tea plants. Apply bud-promoting fertilizers 30–50 days before Spring Tea harvest, accounting for 30%–40% of the annual application. Summer tea top-dressing should be applied before summer tea growth begins, typically in late May to early June, at approximately 20% of the annual amount. Autumn Tea top-dressing should be applied after summer tea harvest, usually in mid-July to early August, also at approximately 20% of the annual amount. Top-dress in shallow trenches between rows (outside the tree canopy), cover with soil afterward, or broadcast on the surface followed by light rotary tillage at a depth of 5–10 cm to ensure thorough mixing of the fertilizer with the soil, preventing leaching.
7. For tea gardens that only harvest spring tea and not summer or autumn tea, the lower limit of the recommended fertilization rates can be used; adjust the annual fertilization plan accordingly, with 60% of the total nitrogen (including both organic and chemical fertilizers) applied as base fertilizer. Before deep (heavy) pruning after the spring tea harvest, apply 20% of the annual nitrogen as top-dressing, and then apply another 20% of the annual nitrogen in late July.
8. Recommend (18–25)–8–12–2 (N–P2O5–K2O–MgO) or similar formula specialized fertilizers, applied in conjunction with organic fertilizers and fast-acting nitrogen fertilizers. Apply specialized formula fertilizers as base fertilizers, recommended at 30–50 kg/acre, with 75–100 kg/acre of cake meal or 200 kg/acre of commercial organic fertilizer. Apply additional nitrogen fertilizer (N) according to different tea types and picking volumes: for high-quality green tea and Oolong tea gardens that only harvest spring tea, supplement with 6–8 kg N/acre; for green tea gardens harvested throughout the year, supplement with 10–16 kg N/acre; for oolong tea gardens harvested throughout the year, supplement with 8–10 kg N/acre; for black tea gardens, supplement with 6–8 kg N/acre.
9. For tea gardens affected by moderate drought, promptly perform light pruning once the drought eases, and spray amino acid-based water-soluble fertilizers and other nutritional foliar fertilizers to promote recovery of the tea plants, and apply base fertilizers slightly earlier than usual.