Growing Potato crop nutrition advice

What soil type, pH and climate do potatoes prefer?

• Potatoes prefer full-sun and well-drained, loose, and friable soil that offers adequate aeration to facilitate root and tuber growth.
• Sandy loam and loamy soils are often well-suited
• Potatoes thrive in slightly acidic to neutral soil that promotes nutrient availability (5.5-6.7 pH)
• Cooler temperatures (59°F to 70°F during the growing season) can help promote optimal tuber development

What nutrients are most important for potato yield and quality?

In addition to required macronutrients, nitrogen (N), phosphorus (P) and potassium (K), potatoes also require calcium, sulfur and magnesium in sufficient quantities to ensure quality crop, reduce instances of scab and promote bulking. Due to their roles in specific growth and physiological processes, secondary macronutrients can be more limiting, affecting both yield and quality. One source that delivers Mg, S and Ca – plus K – is the mineral polyhalite. While other micronutrients are required in lower quantities, balanced nutrition is important for healthy crop growth.

• Potatoes can show a significant response to phosphorus (P) fertilizers even when soil test levels of P are already considered very high for other crops.
• Despite high initial soil P levels, potatoes often need additional phosphorus to achieve optimal yield and quality.
• Phosphorus in soil can become less available to plants, especially at higher soil pH levels, and inefficient phosphorus use can raise environmental concerns.
• Using acidifying water-soluble fertilizers, such as Nova Pekacid and Agrolution pHLow, in nutrient management programs can enhance the availability of phosphorus, release soil nutrient reserves, and improve nutrient efficiency. This approach leads to better quality, increased yields, and more cost-effective results.
• Explore our webinar on phosphorus management for potatoes, including managing soil and fertilizer pH as a tool for increased P availability.
• Secondary macronutrients are crucial for maximizing crop yield and maintaining potato quality, often being as important as Nitrogen (N), Phosphorus (P), and Potassium (K).
• Polysulphate® is a recommended source of secondary macros (low salt, low-chloride K, and source of Ca and Mg).
  • Polysulphate potato trials across five locations (Minnesota, Michigan, North Carolina, Manitoba, and Prince Edward Island) demonstrated yield increases, improved nitrogen-use efficiency, reduced hollow heart, and enhanced fry quality.

Estimated nutrient uptake (kg/t) by: 

Source: IPNI

Role of nutrients

Magnesium (Mg)

• Central component of chlorophyll, essential for photosynthesis and plant growth.
• Influences starch accumulation, contributing to desirable texture and culinary qualities.
• Involved in the activation of various enzymes.

Sulfur (S)

• Vital for the formation of amino acids and proteins.
• Plays a role in photosynthesis and improves nitrogen-use efficiency.
• Crucial for carbohydrate production, impacting tuber development.

Calcium (Ca)

• Helps plants recover from stress conditions such as excessive heat or rain by supporting root regrowth.
• Prevents internal browning and hollow heart, which can affect tuber quality.
• In potatoes particularly, calcium reduces skin problems and internal necrosis. Calcium application through Polysulphate results in improved marketable yield and quality.

Nitrogen (N)

• Essential for overall plant growth, promoting vigorous vegetative development and leaf production.
• Crucial for protein synthesis, which affects tuber yield and quality.

Potassium (K)

• Supports photosynthesis and carbohydrate transport within the plant.
• Enhances tuber size and quality by improving stress resistance and overall plant health.

Phosphorus (P)

• • Important for energy transfer and storage within the plant.
  • Supports root development and tuber initiation, leading to better yields and early growth.

+ = improving

– = decreasing

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

Source: IPI bulletin – Fertilizing for high yield | POTATO 

Nutrient deficiencies

What cultivars are best suited for US growers?

• Choosing potato cultivars well-adapted to local climate and soil conditions enhances overall success.
• Choice depends on various climactic factors, soil types, and the intended crop use (fresh, processing).
• It is important to consult with local agricultural extension services to stay up to date on agronomic advancements.
• Popular US cultivars include Russet Burbank, Russet Norkotah, Yukon Gold, Red Pontiac, Kennebec and various fingerling varieties.

What are common challenges for US potato producers?

Potato producers in the United States face various challenges that can impact the success and profitability of their crops. Some of the most common challenges include:

• Disease and pest management with common issues such as late blight (caused by fungus-like oomycete) and aphids, and Colorado potato beetle
• Nutrient management and soil health to maintain optimal fertility and reduce nutrient imbalances that can affect yield and quality and instances of scab
• Storage and quality maintenance to avoid disease, rot and sprouting

Addressing these challenges often involves a combination of integrated pest management, sustainable agricultural practices, balanced fertility management, and adopting new technologies.

Crop Nutrition Planning

Ultimately, the source of nutrients is crucial—not just the application rate, but also the availability of nutrients within each fertilizer product. This significantly affects yield and can reduce fertilizer costs per acre, enhancing the grower’s return on investment. Secondary macronutrients are vital for both yield and quality and must be incorporated into any crop nutrition plan. Achieving a balanced nutrient supply is key to maximizing potato yields and increasing market value. When selecting fertilizers, it is essential to assess nutrient availability and its impact on overall costs. Reach out to an ICL expert to discuss your crop nutrition planning today.