Strawberry Fertility: Avoiding pH Issues, Salt & Chloride Stress

Strawberry Nutrition: Why Precision Matters

Strawberries may be hardy in flavor, but they’re delicate when it comes to nutrition. From the soil they grow in, to the water they’re irrigated with, strawberries are highly sensitive to several factors—especially chloride, salinity, and soil pH. If we aren’t careful, salinity for example, can have a significant economic impact and result in poor fruit quality, reduced yields, and stunted plants.  

At ICL, we often talk about taking a systems approach, and we recommend tailoring nutrition programs for strawberries by focusing on balanced inputs that are chloride-free, with a low salt index, and suited for high-value, sensitive crops. It’s not just about feeding the crop—it’s about protecting it and proactively preventing issues, too. 

Let’s take a closer look at how to navigate the sensitivities of strawberries and build a program that delivers quality fruit and strong ROI. 

Sensitivity to Chloride and Salinity: What We Need to Know

Strawberries are particularly sensitive to chloride and high salinity—two common issues in coastal and arid regions, like California’s soils and irrigation water. 

Why It Matters:

• High chloride levels, especially from fertilizers like potassium chloride (KCl, 0-0-60 or muriate of potash/MOP), can inhibit nitrate uptake and reduce photosynthesis. This can lead to smaller fruits, poor coloration, and weaker yields. 

• Salinity stress can cause brittle leaves, brown margins, and even root death. Sodium ions in saline water also compete with essential nutrients like potassium, calcium, and magnesium, reducing overall nutrient uptake. 

Solutions We Recommend:

• Choose chloride-free potassium, low salt sources, such as: 

• • Nova® N-K LQ (3-0-10) — a premium, acidic potassium nitrate liquid 

• • Nova HiPeak® (0-44-44) — a high-purity water-soluble straight fertilizer with high concentration of phosphorus and potassium. 

• • Polysulphate® — a natural mineral fertilizer rich in potassium sulfate (sulfate of potash/SOP). 

• Counteract sodium stress with calcium and magnesium, which are found in Polysulphate®. 

• Use acidifying fertilizers like Nova PeKacid® or Agrolution pHLow® to lower pH and improve nutrient uptake. 

• Always monitor irrigation water quality, and ensure your fields have good drainage to reduce salt accumulation around roots. 

Proven Fertilizers for Strawberries: Supporting Healthy Growth at Every Stage

A successful strawberry program starts with season-long nutrition that matches the crop’s needs from transplant to harvest. Here’s how we recommend structuring your fertilizer program: 

Pre-Plant: Controlled-Release and Specialty Granulars

• Agriform® Strawberry Mix — A specialty controlled-release fertilizer (CRF) in a wide range of formulations that aligns with the crop’s nutrient uptake curve. With 100% resin-coated NPK, this mix reduces leaching and improves nutrient use efficiency (NUE). Ideal for setting up the crop for success from day one. 

• Polysulphate® — This OMRI-listed, natural mineral fertilizer contains four essential nutrients—potassium, sulfur, calcium, and magnesium. It supports root development, fruit firmness, and low-chloride potassium supply, all while improving nutrient balance and soil health.

Mid-Season Fertigation and Foliars: Flexible Tools for Critical Stages

As strawberries enter flowering and fruiting, nutrient demands spike. This is the time to fine-tune your inputs for peak performance. 

Acidifying Fertilizers for High-pH Soils and Water: 

• Agrolution pHLow® — Dual-action fertilizer that delivers nutrients while reducing pH in the rhizosphere; available in various formulations. 

• Nova PeKacid® (0-60-20) — A unique phosphate and potassium source with an acidifying effect (pH ~2.2), ideal for use in hard water or alkaline conditions. 

Water-Soluble Options for Targeted Feeding: 

• Nova HiPeak® (0-44-44) — A chloride-free potassium and phosphorus source with neutral pH—ideal for foliar or fertigation applications during high-demand periods. 

• Nova PeaK® (0-52-34) — With a slightly acidic pH and high phosphorus content, Nova PeaK® is well-suited for early bloom and fruit set. 

New Liquid Formulations:

• Nova® N-K LQ (3-0-10) — Formulated specifically for high-pH irrigation water and potassium-demanding crops, this low-salt liquid potassium nitrate delivers fast nutrient uptake with a slightly acidic pH. Key benefits of Nova® N-K LQ: 

• • Chloride-free, low-salt index, safe for sensitive crops 

• • Slightly acidic formulation, ideal for high-pH irrigation water 

• • Rapid, efficient nutrient uptake for optimal plant growth 

• • Flexible application: drip, pivot, foliar, or sprinkler 

Agronomist-Backed Recommendations for Better Strawberry Yields
 

Drawing from our trials and grower feedback across California and North America, here are three key takeaways for optimizing strawberry nutrition: 

1. Prioritize pH Management: Strawberries thrive in slightly acidic conditions. Acidifying fertilizers like Agrolution pHLow® and Nova PeKacid® help unlock nutrients tied up in alkaline soils and improve overall nutrient absorption. Even a slightly acidic formulation line Nova N-K LQ can help improve uptake.  

1. Invest in Long-Term Nutrient Efficiency: Controlled-release fertilizers like Agriform® Strawberry Mix may come with a higher upfront cost but offer season-long benefits—reduced leaching, fewer applications, and more consistent growth. 

1. Use an Integrated Nutrient Program: Begin with pre-plant CRFs and Polysulphate®, then pivot to targeted fertigation and foliar nutrition (Nova) to support flowering and fruit development. This approach delivers balanced nutrition while minimizing stress on sensitive roots. 

Proven in the Field and on the Bottom Line

Our research and field experience show that integrating products like Agriform® Strawberry Mix, Agrolution pHLow ®, Polysulphate®, and Nova® N-K LQ into a strawberry fertility program can significantly reduce the impact of chloride and salt stress. These products not only support healthier root systems and better nutrient uptake, but they also contribute to higher yields, improved fruit quality, and more consistent crop performance. 

By taking a balanced, systems-based approach to fertilization, strawberry growers can protect sensitive crops, optimize nutrient efficiency, and see a stronger return on investment—without compromising on sustainability. 

To learn how these solutions can support your strawberry production and profitability, connect with an ICL agronomist or speak with one of our California-based experts today.