1、Potassium Management for Optimizing Citrus Production and Quality: International Journal of Fruit Science: Vol 6, No 1

The current recommendations on the application of soil and leaf analysis for evaluation of the K nutritional status and guidelines for K fertilization are also discussed.

2、Phosphorus and potassium soil test and nitrogen leaf analysis as a base for citrus fertilization

A network of six NPK long-term field trials was carried out on different soils of citrus-producing regions of São Paulo state, Brazil, in order to estimate quantitative relations of fruit yield to NPK fertilization and to determine parameters for fertilizer recommendation based on soil testing and leaf analysis.

3、Influence of irrigation system and fertilization management on seasonal distribution of N in the soil profile and on N

Understanding the fate of nitrogen (N) in agricultural soils as affected by crop N uptake is important in order to develop management practices that maximize nitrogen uptake efficiency by minimizing N losses.

4、A New Nitrogen and Potassium Fertilization Management Program for Clementine Mandarin under Mediterranean Climate

Leaf analysis is a useful tool to evaluate the nutrient status of citrus trees, but diagnosis standards for ‘Clementine mandarin’ are not available.

5、Fruit yield and quality of sweet oranges affected by nitrogen, phosphorus and potassium fertilization in tropical soils

The influence of cultivar and high nitrogen and potassium fertilization on fruit quality traits of young orange trees, Proc. Fla. Sta. Hortic. Soc. 106 (1993) 8–12.

Nitrogen, Phosphorus and Potassium Fertilization Interactions on the Photosynthesis of Containerized Citrus Nursery Trees: Journal of Plant Nutrition: Vol

The objective of this research was to evaluate the nitrogen, phosphorus and potassium (NPK) fertilizer effect on the development of ‘Valencia’ sweet orange nursery trees budded on Rangpur lime rootstocks in a greenhouse using containers.

Effects of Different Fertilization Treatments on Soil, Leaf Nutrient and Fruit Quality of Citrus grandis var. longanyou

The five-year-old “Longanyou” trees were used as the experimental material to study the effects of different fertilization treatments. The nutrient contents in soil and leaves, fruit yield and quality were determined, and then the correlations were analyzed.

Fertigation: Concept and Application in Citrus

In this sense, farmers should use the information about the annual requirements established for citrus trees to adopt the optimum nutrient dose. These N requirements may be adjusted according to the nutrient uptake efficiency of fertilizers.

Response of Young Citrus Trees on Selected Rootstocks to Nitrogen, Phosphorus, and Potassium Fertilization

A network of field experiments was conducted to study the differential response of young sweet orange trees on selected rootstocks to nitrogen (N), phosphorus (P), and potassium (K) fertilization. The application of soil and leaf analyses to develop optimal fertilizer recommendations was evaluated.

Integrated Nutrient Management in Citrus

Citrus by its avid nutrient-absorbing capacity, is considered a highly nutrient-responsive perennial fruit crop. Differential efficacy of two conventional methods of fertilization (soil versus foliar application), although helped in improving the quality citrus, but...

Citrus trees, also known as orange trees, are important fruit-bearing plants widely cherished for their delicious and nutritious fruits. During their cultivation, reasonable fertilization is a critical measure to improve yield and fruit quality. As one of the three essential macronutrients for plant growth, potassium fertilization significantly impacts the development of citrus trees and fruit quality. Below are the best practices for applying potassium fertilizer to citrus trees:

1. Determine the Optimal Fertilization Period

Fertilization should follow the principle of "timely and appropriate application." Spring and autumn are the most suitable periods for fertilization. Spring fertilization promotes new shoot growth and flower bud differentiation, while autumn fertilization supports fruit expansion and maturation.

• Spring: The first application is typically carried out before budbreak in early spring, dominated by nitrogen fertilizer to encourage new shoot growth. Subsequently, adjust the ratio of phosphorus and potassium fertilizers based on tree vigor and soil fertility to enhance flower bud differentiation.
• Autumn: After fruit harvest, apply a second round of fertilization (primarily organic fertilizers) based on soil test results and tree needs. This replenishes nutrients, strengthens root systems, and prepares the tree for the next growing season.

2. Select Appropriate Potassium Fertilizer Types

Potassium is vital for citrus growth, improving fruit quality and pest resistance. Consider the following when choosing potassium sources:

• Origin: Organic options like plant ash or animal manure are rich in potassium. Chemical fertilizers such as potassium sulfate or potassium chloride can also be used, selected based on soil conditions and cost-effectiveness.
• Ratio: In spring, prioritize nitrogen with supplementary phosphorus and potassium. In autumn, focus on phosphorus and potassium while reducing nitrogen to balance nutritional needs across seasons.

3. Apply Potassium Fertilizer Effectively

Proper application methods maximize efficiency and minimize risks:

• Depth and Distance: Apply potassium fertilizer deeply near the root zone to facilitate absorption, avoiding direct contact with roots to prevent damage.
• Uniform Distribution: Ensure even spreading to avoid localized over-concentration, which may cause root burn or nutrient imbalance.

4. Control Fertilization Amount and Frequency

Adjust dosage and frequency according to the tree’s growth stage and soil fertility:

• Young Trees/Early Fruiting: Higher potassium requirements to support shoot and fruit development.
• Mature Trees: Moderate potassium use to avoid overly heavy fruits.

5. Integrated Management

Potassium fertilization is just one aspect of optimizing citrus quality. Combine it with other practices:

• Water management, pruning techniques, and pest control to achieve high-quality, high-yield production.

rational potassium application is crucial for citrus growth and fruit quality. By selecting suitable fertilizers, timing applications properly, controlling doses, and integrating comprehensive management, farmers can significantly improve both yield and fruit excellence.