Citrus (orange, mandarin, lemon, grapefruit) is one of the Mediterranean's most important crops, and as a perennial tree its nutrition must be planned within an annual cycle. The right program directly affects flowering, fruit set, fruit size, colouring, and sugar content. This guide presents a stage-by-stage citrus fertilization program with product recommendations.
The Foundation: Soil Analysis
Citrus orchards are mostly on calcareous, high-pH soils, which hinders the uptake of trace elements, especially iron. So the program should start with a soil analysis, with results interpreted by our agricultural engineers.
Fertilization Program by Growth Stage
1. Spring Shoot and Flowering Stage
At bud break and flowering, the goal is balanced nutrition and strong shoots. Power NPK supplies macronutrients with organic components. Citrus is frost-sensitive; under late spring frost risk, AminoWork improves stress resistance, and at flowering it reduces flower drop.
2. Fruit Set Stage
In this critical set-determining stage, amino acid support along with boron and zinc matters. An application of AminoWork reduces physiological drop and improves set.
3. Fruit Growth Stage
Balanced nutrition continues for fruit size, with potassium increased gradually. For stress resistance, peel quality, and trace-element uptake, seaweed-based RapidAlg is beneficial.
4. Ripening and Colouring Stage
Potassium drives sugar accumulation, peel colour, and fruit quality, so potassium-led nutrition is preferred and nitrogen is reduced. This balance improves the acid-sugar ratio and shelf life.
5. Post-Harvest
After harvest, the tree's nutrient storage is critical for next year's flowering and yield. Balanced support prepares the tree strongly for the new season.
Common Nutrient Problems in Citrus
- Iron chlorosis: very common on calcareous soils; young leaves yellow between veins while veins stay green. Quickly corrected foliarly with FerroPlus (chelated iron).
- Zinc and manganese deficiency: shows as small, narrow leaves and weak shoots; corrected with a foliar trace-element program.
- Copper deficiency: for weak shoot tips, apply DoraCop foliarly; see the copper deficiency guide for symptoms.
Application via Fertigation
In drip-irrigated citrus orchards, delivering nutrients directly to the root zone saves water and fertilizer. For EC/pH management and scheduling, see our fertigation guide, and for ratio selection the NPK selection guide.
Quality in citrus comes from balanced nitrogen, well-timed potassium, and effective trace-element management (especially iron) on calcareous soils.
For a program tailored to your orchard and species, contact us; share your soil analysis and we will build the plan together.
