1、SL382/SS584: Calcium (Ca) and Sulfur (S) for Citrus Trees

Calcium is the most abundant mineral element by weight in citrus trees, accounting for approximately 1% of tree dry weight. Most Ca resides in the leaves, but fruit also contains Ca at a level of approximately 4.4 lb. per 100 boxes of oranges.

2、How To Get Calcium And Magnesium Into Citrus Foliage

For effective calcium penetration during the fruit cell division period, Sysstem-CAL is recommended, especially for its foliar application benefits. Calcium constitutes approximately 1% of the dry weight in citrus trees, with significant amounts stored in leaves and fruit.

3、Effect of Calcium Fertilization on Calcium Uptake and Its Partitioning

To explore the impact of Ca fertilizer application on plant growth and its allocation among different fractions, young citrus trees were fed over a complete vegetative cycle with a 44 Ca labeled fertilizer (T1-Ca), while control plants (T2) received no Ca fertilizer.

Nutrition

For citrus trees to be healthy and productive, they require a range of mineral nutrients or elements which they extract from the soil. The level or concentration of these mineral nutrients in the leaves closely reflects the nutrient level in the plant and affects its vigour, health and fruitfulness.

Crop Guide: Citrus Plant Nutrition

It is common to sample spring flush of healthy, undamaged leaves that are 4-6 months old on non-fruiting branches (Fig 2a). Selecting leaves that reflect the average size leaf from the spring flush. Typically, 75 to 100 leaves from a uniform 5-hectare block of citrus are sufficient for testing.

USING FERTILIZERS & MANURE IN CITRUS

The following can be used as a guide for fertilizing non-bearing citrus trees in the absence of a soil or leaf test. ... contains calcium and magnesium) at a rate of 1⁄4 lb (114g) per tree, twice per year. Also, add 1⁄4 lb (114g) of Epsom Salts (m gnesium sulphate) per tree, once per year. Trees

(PDF) Effect of Calcium Fertilization on Calcium Uptake and Its

To explore the impact of Ca fertilizer application on plant growth and its allocation among different fractions, young citrus trees were fed over a complete vegetative cycle with a 44 Ca...

Managing Calcium Demand in Citrus

To determine how much calcium might be needed during fertilization, we can look at crop uptake and removal and calculate total calcium demand based on how much calcium is in the plant and how much is removed in the fruit.

Citrus Fertilizer Management: Nutrient Requirements and Application

Nutrients needed include nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, manganese, zinc, copper, boron, molybdenum, and chlorine. The amount and ratio of these nutrients vary depending on the citrus type, age, growth stage, soil type, and climate.

Calcium in Citrus Trees – GrowScripts

Learn why calcium is essential for citrus trees, how to spot deficiency symptoms, and the best ways to treat and prevent calcium-related issues.

In agricultural production, the rational use of fertilizers is key to improving crop yield and quality. Foliar fertilization is an efficient and convenient method for supplying nutrients, allowing plants to quickly absorb essential elements. selecting the appropriate fertilizer type and application method is crucial. For citrus trees, calcium sulfate is a commonly used foliar fertilizer, but it must be applied in proper amounts to avoid nutrient toxicity.

I. Understanding the Characteristics of Calcium Sulfate

1. Chemical Properties: Calcium sulfate is a white, crystalline powder with strong alkalinity. It is soluble in water, forming hydrated calcium sulfate, a type of soluble salt.
2. Agricultural Applications: In agriculture, calcium sulfate is often used as a slow-release/controlled-release fertilizer. It binds with soil calcium ions to release nutrients gradually, meeting plant growth demands.
3. Precautions: Calcium sulfate is unstable in acidic environments, where it may decompose into hydrogen gas and sulfate ions. Avoid mixing or contacting it with acidic substances.

II. Clarifying Application Objectives

1. Promoting Citrus Growth: For growth stimulation, choose compound fertilizers rich in calcium and other nutrients.
2. Improving Fruit Quality: To enhance fruit quality, select foliar fertilizers containing potassium, magnesium, and other microelements beneficial to citrus development.
3. Disease Prevention: For pest/disease control, use fertilizers containing copper, zinc, and other microelements that boost plant disease resistance.

III. Determining Application Concentration

1. Growth Stage of Citrus Trees: Nutrient needs vary by growth stage. Seedlings may require more nitrogen for growth, while fruiting trees need phosphorus and potassium for fruit development.
2. Tree Health Status: If trees exhibit stunted growth or yellowing leaves, target missing nutrients with specific foliar fertilizers to alleviate deficiencies.
3. Recommended Dosage: Follow product guidelines, typically 5-10 kg of calcium sulfate per mu (0.067 hectares). Adjust based on field conditions.

IV. Application Methods

1. Dilution Ratio: Mix calcium sulfate with water at a 1:9 ratio (1 gram of fertilizer + 9 grams of water) to prevent nutrient burn.
2. Timing: Apply in the morning or evening when temperatures are cool and transpiration is low. Avoid peak heat to prevent stress.
3. Uniform Spraying: Ensure full coverage of leaves and stems using sprayers or manual methods. Thorough contact maximizes efficacy.
4. Safety Measures: Wear protective gear (gloves, goggles) due to potential irritation. Avoid contact with eyes, skin, or ingestion.

V. Monitoring Effects

1. Plant Response: Observe for symptoms like leaf yellowing or wilting, which may indicate excessive concentrations. Discontinue use if issues arise.
2. Efficacy Evaluation: Reassess plant health after one week. Robust growth suggests effectiveness; otherwise, adjust dosage or switch fertilizers.
3. Data Recording: Track metrics such as leaf color, flower count, and growth rates to refine future applications and optimize strategies.

VI. Handling Residual Fertilizer

1. Storage: Store unused calcium sulfate in a cool, dry place away from sunlight and moisture to prevent caking or degradation.
2. Misuse Prevention: Keep out of reach of children/pets. Avoid mixing with other pesticides or fertilizers to prevent chemical reactions.
3. Recycling: Reuse residual fertilizer for compatible crops after confirming suitability through testing or expert consultation.

effective use of calcium sulfate for citrus foliar fertilization requires tailoring fertilizer types and concentrations to growth stages, following proper application protocols, and monitoring outcomes. With scientific management, this practice can enhance citrus growth, fruit quality, and sustainability goals.