The 4Rs of Nutrient Stewardship

The 4Rs of Nutrient Stewardship represent a management practice that can help growers enhance crop quality and profitability, reduce nutrient loss, maintain soil fertility and promote sustainability.

Simply put, the 4Rs involve the efficient use of fertilizer by employing the:

  1. Right Source
  2. Right Rate
  3. Right Time
  4. Right Place
The Right Source means using fertilizer inputs that best match the crop’s nutrient needs and soil properties.

Protassium+® sulfate of potash (0-0-50-17S) is a premium K source. With high-quality potassium, virtually no chloride and the added benefit of sulfate sulfur, Protassium+ fertilizer  helps foster plant health and productivity.

The Right Rate means applying inputs to match soil supply and plant demands.

Your crop advisor or fertilizer supplier can help you determine the right amounts of nutrients to apply. For a handy, effective guide, click here to find a calculator that shows recommended fertilizer levels needed to promote an ideal crop, based on nutrient depletion and availability.

The Right Time means ensuring a nutrient is available when the crop most needs it.

Optimal timing of fertilizer applications will vary by crop, soil, weather and other factors, including the nutrients themselves. It is critical to remember that application must proceed demand for that nutrient, and understanding crop uptake patterns will help. For example, a high-quality K source like Protassium+ SOP can be applied pre-plant will ensure that enough K is available during high K crops use during tuber bulking.

The Right Place means applying your fertilizer in the location where you maximize a plant’s access to it, while also minimizing nutrient loss and waste from leaching or runoff.

Protassium+ SOP is available in many sizes of granules as well as in liquid forms, giving you options to position a fertilizer application close to the crop’s root zone and irrigation.

Endorsed and supported by the International Plant Nutrition Institute, The Fertilizer Institute, The Canadian Fertilizer Institute, and the International Fertilizer Industry Association, the benefits of the 4Rs of nutrient management include:1

  1. Optimizing nutrient management
  2. Higher yields
  3. Greater fertilizer efficiency
  4. Minimizing environmental impact

An article on the USDA website featuring John Myers, a state resource conservationist with the USDA’s Natural Resources Conservation Service in Iowa, said that, “the 4R concept considers productivity, profitability, cropping system durability and a healthy environment.”2

Adopting the 4R strategy is especially important when it comes to potassium for specialty crops – in particular, the source a grower chooses. Some K sources are high in chloride, which can be detrimental to chloride-sensitive plants by causing:

  • Poor germination 
  • Nutritional imbalances
  • Seedling injury
  • Tip burn
  • Stunted root and shoot growth

Fortunately, Protassium+ sulfate of potash (0-0-50-17S) is virtually chloride-free and fits the requirement of “Right Source” perfectly. Plus, Protassium+ fertilizer offers the benefit of sulfur in the sulfate form, which is immediately available for plant uptake.


1 Nutrient Stewardship

2 Johnson, Jason, 2011. 4Rs Right for Nutrient Management.