Organic fertilizers suitable for fruit cultivation should be selected comprehensively based on the type of fruit, soil conditions, and growth stage. The following are recommended common and effective types:
1. Mature Compost

• Characteristics: Balanced nutrients (NPK + micronutrients), improves soil structure, enhances water retention.

• Best for: Nearly all fruits (e.g., apples, pears, citrus), especially as a base fertilizer or to enrich poor soil.

• Note: Must be fully decomposed to avoid root burn from unfermented materials.

2. Vermicompost (Worm Castings)

• Characteristics: Rich in nutrients (humic acid, microbes), neutral pH, gentle on plants.

• Best for: Shallow-rooted fruits like strawberries, blueberries, or when soil aeration needs improvement.

• Application: Mix directly into soil or use as a top dressing.

3. Oilseed Meal (Soybean/Rapeseed Cake)

• Characteristics: High in nitrogen and phosphorus, promotes flowering and fruit development.

• Best for: Grapes, peaches, kiwifruit, and other fruit trees requiring phosphorus for flowering.

• Note: Ferment before use to prevent heat damage from raw cakes.

4. Animal Manures

• Chicken Manure: High in nitrogen; suitable for seedlings or leafy crops. Use with磷钾肥 (PK fertilizers) during fruiting.

• Cow/Sheep Manure: High carbon-to-nitrogen ratio, decomposes slowly. Ideal for deep-rooted trees like apples and pears.

• Caution: Always compost thoroughly to avoid pest infestations.

5. Soil-Specific Amendments

• Acidic Soil: Pine needle compost or sulfur (for blueberries, citrus).

• Alkaline Soil: Wood ash (adds potassium but raises pH; suitable for pomegranates, jujubes).

• Calcium Deficiency: Lime-treated compost (prevents bitter pit in apples).

6. Green Manures

• Examples: Chinese milk vetch (Astragalus sinicus), alfalfa (Medicago sativa).

• Use: Till into soil after flowering to boost organic matter, ideal for fallow periods or intercropping.

Application Tips:

• Base Fertilizer: Use compost/vermicompost (60-70%) with a small amount of oilseed meal.
• Top Dressing: Apply high-phosphorus/potassium meals or liquid fertilizers (e.g., fermented fruit peels) during flowering/fruiting.
• pH Adjustment: Test soil every 1-2 years and adjust based on fruit requirements.

Adjust formulations for specific fruits (e.g., citrus needs calcium, blueberries prefer acidity) and combine with inorganic fertilizers (e.g., potassium sulfate) for optimal results.