Growing Pecans – Crop Nutrition 101

What you need to know about pecan fertilization, best practices, and more

Crop Nutrition Information for Growing Pecans (Carya illinoinensis):

  • The pecan, Carya illinoensis, belongs to the Juglandaceae, family which includes several species of trees known for their edible nuts, including walnuts and hickories.

  • Ideally leaf samples should be taken in July for analysis

  • Fertilization depends on soil test and leaf analysis

  • Soil tests should be taken in the year of establishment then every 2 years thereafter

  • The most accurate indicator of orchard fertility is the nutrient status of the leaves

Pecans
Pecan Harvest in Alabama

What soil type, pH and climate do pecans prefer?

  • Pecans prefer deep, well-drained soils that are fertile and loamy, allowing for good root development. Ideally, sandy loam or loamy sand with clay subsoil see some of the best growth
  • Pecans thrive in slightly acidic to neutral soil pH levels, ideally between 5.5 and 6.5. Magnesium deficiency is best prevented by maintaining soil pH at 6.0-6.3.
  • Pecans prefer regions with long, hot summers and mild winters. They require a significant amount of heat during the growing season to produce nuts successfully. Generally, they are well-suited to areas with a humid subtropical or temperate climate.
  • Proper orchard spacing and canopy management are crucial for maximizing pecan yield and quality. Pruning and thinning of overcrowded trees enhance light penetration within the canopy, which improves fruiting and reduces disease incidence.

Water Management

  • Effective water management is critical for pecan production, especially in regions with variable rainfall patterns or limited water resources. Balancing water availability with orchard water needs requires efficient irrigation systems and scheduling practices.
  • Adequate soil moisture is critical during key stages like bud break, nut sizing, and nut filling to ensure optimal growth, nut size, and quality.
  • Despite their deep roots, pecan tress primarily use water from the upper layers of the soil. When pecan trees do not have adequate water and are forced to access deeper water resources it can result in leaf shedding, nut drop, and/or lower quality nuts.
  • Water management plays a critical role in nutrient management and fertilization for pecan growers by optimizing nutrient availability, enhancing fertilizer efficiency, supporting root health, and ultimately maximizing yield and nut quality.
  • Adopting soil moisture monitoring, scheduling irrigation and implementing efficient irrigation systems such as drip irrigation or micro-sprinklers can optimize water use and reduce water stress.

Key Nutrients:

Pecans require several macronutrients (N, P, K, Mg, Ca, S) and micronutrients (Zn, Fe, Mn, B, Cu, Ni) for optimal growth and fruit production. Nutrient deficiencies, especially nitrogen, potassium, and magnesium, are common in Georgia soils. Normal leaf concentrations should be: N 2.3 and 3.0%; K .75 – 1.75%.

  • Nitrogen(N) is essential for tree growth, yield, and kernel quality and is the most limiting nutrient, and most likely to become deficient. Tell-tale signs of deficiency include poor growth, reduced yield, and pale leaves.
    • Fertilization Tips:
      • Soil Application: Apply in early spring or split applications in spring and late summer.
      • Foliar Application: Can be effective during early growth stages or during periods of deficiency.
      • Fertigation: Suitable for irrigated orchards, allows precise nitrogen application.
      • Techniques: Monitor soil moisture to optimize nitrogen uptake; avoid excessive application to prevent foliage shading.
  • Potassium (K) facilitates carbohydrate movement, regulates osmosis, and enhances winter resistance and is the second most important nutrient in pecan production after N. Deficiencies can often be recognized by leaf scorch and reduced shoot growth.
    • Fertilization Tips:
      • Soil Application: Apply Polysulphate as an alternative to potassium chloride (muriate of potash) in early spring. Polysulphate contains important secondary macros, like calcium, magnesium and sulfur and is a low-chloride source of K.
      • Foliar Application: Beneficial during early growth stages or when deficiency symptoms appear, Nova FLOW and Nova PULSE are good examples, of potassium rich foliar solutions that also include key micronutrients like Zinc and Boron
      • Techniques: Maintain a balanced nitrogen-potassium ratio (2:1); adjust application based on leaf analysis.
  • Micronutrients:
    • Pecan trees are heavy users of Zinc; it is essential for quality and yield. Zinc is often applied as a foliar spray to ensure quick uptake.
  • Using fertigation solutions that contain a fully chelated micronutrient pack, and a balanced NPK supply can support integrated nutrient management. Depending on soil pH and water quality, Agrolution (non-acidifying) or Agrolution pHLow (ideal for alkaline soils/hard water) are powerful fertigation solutions that come in a range of analyses to meet crop and soil needs.

Nutrient Requirements:

 

Nutrient balance is key to quality yields. Based on lbs/acre, these are the essential nutrients requirements (Wells & Conner, 2007)

Element Sufficiency Range

  • N(%) 2.5-3.0
  • P (%) 0.14-0.3
  • K(%) 1.3-2.5
  • Mg(%) 0.35-0.6 Ca(%) 1.3-1.75
  • S (%) 0.25-0.5
  • Zn (ppm) 50-100
  • Fe (ppm) 50-300 Mn (ppm) 100-800 B (ppm) 50-100
  • Cu (ppm) 6-30

Role of Nutrients:

Key quality and yield parameters can be affected by different nutrients. See how they can influence your harvest.

+ = improving    – = decreasing    +/- = different results, depending on the rate of nutrient applied

Yield: N++, P+, K+, Mg+, Ca+, S+ Quality: N+, P+, K++, Mg+, Ca+, S+

 

General Tips for Fertilization:

  • Leaf Analysis: Use foliar or leaf analysis to adjust nutrient application rates and timing.
  • Timing: Apply nutrients during critical growth stages (e.g., early spring, kernel filling) to meet tree demands.
  • Integration: Combine soil, foliar, and fertigation methods based on orchard needs and environmental conditions.
  • Monitoring: Regularly monitor soil conditions, pH levels, and leaf nutrient status to optimize nutrient uptake and tree health.
  • Balanced Approach: Maintain a balanced nutrient profile to prevent deficiencies and maximize pecan production.

Pecan trees have specific periods of high nutrient demand, such as during early spring foliage growth and kernel filling stages. Matching nutrient application timing with these demand periods is essential for optimizing tree health and nut production.

 

Q&A

  • During the growth of the crop, leaf tissue analysis are the best available tools to determine e whether the crop is taking up sufficient nutrients to be corrected by side dressing or foliar application if necessary. Leaves should be sampled for analysis between July and August as this is the time the nutrient in the leaves are most stable. 

  • Pecans love Zinc, and it is generally applied with a foliar application. Young and fastgrowing trees need Zinc in the spring at budbreak, continuing for three sprays in 2-3 week intervals. 

Need expert advice on your plant nutrition plan?

Proven in Pecans

Polysulphate®

Exceptional natural multi-nutrient fertilizer

Polysulphate Granular

0-0-14
+TE

See product

Nova

The perfect solution when your crops need a boost of water-soluble phosphorus and potassium

Nova PeKacid 0-60-20

0-60-20

See product

Agrolution pHLow

A dual-purpose water-soluble fertilizer that tackles water quality challenges and supplies high phosphorus plus zinc

Agrolution pHLow 11-45-11 +Zinc Starter

11-45-11

See product

Nova

A highly soluble alternative to magnesium nitrate with N-P-K, plus magnesium, sulfur, and boron.

Nova FLOW (5-10-20 +9Mg)

5-10-20

See product

Nova

Get your plants off to a quick start with MagPhos

Nova MagPhos 0-55-18+4.21Mg

0-55-18
+TE

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Nova

A unique cobalt and molybdenum foliar fertilizer to improve nitrogen efficiency and take your crops to the next level.

Nova ELEVATE (1.2 Co + 26 Mo)

0-0-0

See product

Nova

A dual-purpose, high phosphorus liquid fertilizer addresses water quality issues plus provides Zn for enhanced root growth

Nova PeKacid LQ 4-17-4 +Zn



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Agroblen® Total

A controlled-release fertilizer provides a balanced supply of NPK plus S to deliver precision crop nutrition for up to six months

Agroblen® Total Balanced 14-14-14 (5-6M)

14-14-14

See product

Agrocote®

A premium quality potassium sulfate fertilizer that offers controlled release for up to 4 months

Agrocote® SOP 0-0-48 (3-4M)

0-0-48

See product