Chinese jujube (Ziziphus jujuba), a deciduous shrub, is widely cultivated for its fruit, the red jujube. During its growth, it requires ample nutrients to support healthy development and high yields. Foliar fertilization is an effective method to supplement plant nutrition, particularly when soil nutrients are insufficient or during critical growth periods. Below, we introduce several foliar fertilizers suitable for the late growth stage of Chinese jujube, along with guidelines for proper application.

I. Potassium Dihydrogen Phosphate

1. Primary Functions: Potassium dihydrogen phosphate (KH₂PO₄) is a common nutrient supplement containing phosphorus and potassium. Phosphorus promotes root development and enhances disease resistance, while potassium regulates water balance, improves stress tolerance, and boosts photosynthesis.
2. Application Method: During the late growth stage, especially in dry or hot conditions, apply KH₂PO₄ via foliar spraying every 7–10 days for 3–4 consecutive applications. Avoid direct contact between the solution and leaves to prevent scorching.
3. Precautions: Excessive use may cause root burning. Strictly control dosage and frequency. Consider varietal differences, as nutritional needs may vary by jujube type.

II. Micronutrient Fertilizers

1. Primary Functions: Micronutrients like iron, manganese, zinc, copper, and boron are essential for growth, even in small quantities. They play critical roles in physiological processes.
2. Application Method: Apply micronutrient solutions as foliar sprays. Dilute according to product instructions (typically 1:500–1:1000) and ensure even coverage across all leaf surfaces.
3. Precautions: Avoid mixing with high-concentration nitrogen fertilizers to prevent chemical reactions. Consult experts before application, as different micronutrients have distinct mechanisms.

III. Organic Fertilizers

1. Primary Functions: Organic fertilizers (e.g., animal manure, green manure) enrich soil with organic matter and trace elements, improving structure, water retention, and fertility.
2. Application Method: Apply as base fertilizer pre-planting or as topdressing. Combine with synthetic fertilizers or spray directly on leaves. Due to slow decomposition, use moderate amounts and frequencies.
3. Precautions: Avoid mixing with chemical fertilizers to prevent absorption interference. Ensure compliance with local environmental and agricultural regulations.

Selecting appropriate foliar fertilizers during the late growth stage is crucial for enhancing yield and quality in Chinese jujube. Potassium dihydrogen phosphate, micronutrient fertilizers, and organic options each offer unique benefits. Tailor choices to specific growth needs and soil conditions. Proper use of foliar fertilizers ensures nutrient adequacy, stress resilience, and improved productivity.