Start your Citrus off Right this 2022 Season - Focusing on Calcium and Phosphorus

January 2022

Another year has passed, and we are well into the citrus harvest. Before too long we will see trees blooming once again and the farming season will be in full swing. Changes in fertilizer and crop prices, as well as water restrictions, have many farmers searching for new ways to maintain profitability.

Having a strong, balanced nutrition program is important when growing any agricultural crop. Providing all essential nutrients when the crop demands them is critical in order to achieve high yields, quality, and profitability. A balanced nutrition program will also ensure that you maintain overall tree and soil health.

Calcium and phosphorus are two essential nutrients that you might consider applying in early spring. Calcium is a critical component of cell walls and has a direct influence on the regulation of enzyme systems and nutrient uptake. Calcium also influences pollen tube elongation and seed formation. Phosphorus supports better root growth and is a key component in energy production and transfer in cells. Phosphorus captures, stores, transports, and releases energy for metabolic processes. Both calcium and phosphorus increase cell division, improve root growth and play major roles in photosynthesis.

P deficiency - citrus old leaf.png Phosphorus deficiency - old citrus leaf

P def young leaf.png Phosphorus deficiency - young citrus leaf

Stunted, poor growth is a common sign of a phosphorus deficiency. Visible symptoms also include purplish and bronze discoloration on leaves. Leaves will shed prematurely, and fruit drop can be heavier in these conditions. Phosphorus deficiencies can impede flower development thus reducing fruit set and yield. A deficiency in calcium is exhibited as marginal and sometimes interveinal chlorosis as well as poor, uneven terminal growth. Calcium deficiency also leads to reduced yield and poor-quality fruit. Citrus trees with severe deficiencies will have weak cell structures, lack vigor, and can develop twig dieback.

Phosphorus and calcium uptake occurs throughout the growth period, after flowering and through late fruit maturity. Sufficient availability is critical during periods of active root growth such as early spring and in between vegetative flushes. We have to remember that plants require a balanced approach to providing ALL essential nutrients, not just phosphorus and calcium. Refer to your most recent analytical reports and a Yara Agronomist to help you put together a more targeted and efficient citrus crop program.

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Yara's Solutions for Citrus Nutrition

Leffingwell® Nutra-Phos® CalZinc 0-24-0 and Leffingwell® Nutra-Spray® ZM are fully formulated foliar-applied products providing great solutions for early vegetative and spring flush nutrition.

  • High analysis, pH neutral, wettable powder that provides the essential nutrients over several days giving a cost-effective treatment.
  • Extremely fine particle size gives thorough coverage, efficient nutrient uptake, and enhanced sprayability.

Leffingwell Nutra-Phos CalZinc - 24% P, 20% Ca, 6% S, 12% Zn
Leffingwell Nutra-Spray ZM - 10% Ca, 7% Mn, 18.5% Zn

YaraLiva® CN-9® and YaraLiva® TROPICOTE® provide immediately available nitrate-nitrogen and water-soluble calcium.

  • Nitrate nitrogen increases plant growth by enhancing the uptake of other essential nutrients such as calcium, magnesium, and potassium
  • Water-soluble calcium promotes proper cell division for larger fruit and less chance of disorders such as creasing
  • Readily available calcium promotes root growth for efficient water and nutrient uptake


Contact your local Yara representative to find a distributor of these products near you.

Vanessa Vicencio

Sales Agronomist at Yara North America - South Central Valley, California

Read the latest California Citrus Newsletter


Vanessa Vicencio
Vanessa Vicencio
Sales Agronomist

South Central Valley, California