After the spring dormancy breaking stage, citrus trees enter the flowering-to-fruit-set phase, marking the transition from vegetative growth to reproductive growth. This critical stage is influenced by environmental factors and requires a balanced nutrient supply to ensure healthy fruit development. To achieve this, monitoring plant conditions and performing leaf analysis is recommended, with particular focus on the following nutrients:
Key Nutrients for Flowering to Fruit Set Stage:
- Nitrogen (N): Essential for flower bud development and fruit set. However, excessive nitrogen can lead to excess vegetative growth, diverting energy away from flowers and fruit, resulting in fewer flowers and reduced fruit production.
- Phosphorus (P): Crucial for energy transfer, flower formation, and fruit quality during this stage.
- Potassium (K): Supports fruit quality by playing key roles in enzyme activation, cell division, growth, water regulation, and stress resistance.
- Calcium (Ca): Important for pollen tube elongation and seed formation.
- Zinc (Zn): Prevents premature leaf drop and promotes healthy bud development.
- Manganese (Mn): Increases the number of fruits per tree, boosting yield.
- Iron (Fe): Prevents fruit set restrictions and supports fruit size.
- Boron (B): Vital for flower initiation and pollen germination.
Learn more about Plant Nutrients and Their Functions
Nutrient Supply Recommendations for the Vegetative Growth Stage (60 ton/ha expected yield):
- Nitrogen (N): Apply ~27% (77 Kg/ha) of the annual requirement (286 Kg/ha).
- Phosphorus (P₂O₅): Apply ~22% (21 Kg/ha) of the annual requirement (96 Kg/ha).
- Potassium (K₂O): Apply ~13% (35 Kg/ha) of the annual requirement (272 Kg/ha).
The following table, generated by Haifa's NutriNet tool for crop nutrition management, shows the annual nutrient requirements of citrus.
| Macronutrients | secondary Nutrients | Micronutrients | ||||||||||
Stage | days | N | P2O5 | K2O | CaO | MgO | Fe | Mn | Zn | Cu | Mo | B |
Vegetative growth | 60 | 55 | 15 | 25 | 0 | 5 | 0.057 | 0.057 | 0.027 | 0.023 | 0.0015 | 0.015 |
Flowering to fruit set | 60 | 77 | 21 | 35 | 0 | 7 | 0.129 | 0.129 | 0.062 | 0.052 | 0.003 | 0.03 |
Fruit development | 120 | 118 | 48 | 164 | 48 | 12 | 0.321 | 0.321 | 0.153 | 0.13 | 0.0075 | 0.075 |
Harvest to final | 120 | 36 | 12 | 48 | 0 | 0 | 0.016 | 0.016 | 0.008 | 0.0065 | 0.0004 | 0.004 |
Fertilization Strategies for Maximum Citrus Yield
To maximize citrus crop profitability, precision fertilization is key. The best results are achieved through the following strategies:
- Nutrigation™ (Fertigation): Use water-soluble fertilizers combined with micronutrients for efficient and precise nutrient delivery.
- Controlled-Release Fertilizers (CRFs): Apply CRFs for continuous nutrient availability through soil application, ensuring steady plant nourishment throughout the growing season.
- Foliar Nutrition: Use Haifa’s specialized fertilizers and micronutrients for foliar applications to enhance plant performance and prevent deficiencies during the vegetative stage.
Explore NutriNet™ for a tailored full-season fertilization program.
