Understanding your crop’s needs and asking the right questions are critical to developing an effective vegetable nutrition program.
Vegetable growers obviously understand the importance of effective nutritional applications to produce maximum marketable yield, but many growers’ nutrition programs miss the mark because their program doesn’t adequately address all the components that drive a Science-Based Nutritional Program.
“Plant nutrition is based upon plant physiology, which is the science of how different nutrients are used by the plant,” explains Ken Dart, National Technical Manager for Agro-K. “The best nutrient programs follow the concept of the what should be called the Five Rs.”
Dart identifies the Five Rs as applying:
- Right nutrient
- Right time/crop stage
- Right form (this is especially true when dealing with foliar nutrition, because the product formulation will dictate how completely and quickly the nutrient goes into the plant tissue and is able to be used by the crop.
- Right nutrient mix. (Not all nutrients work well together in the plant at the same time)
- Right place in the plant. (Roots vs. leaves or fruit for example)
“Growers are becoming more sophisticated, especially those producing high-value vegetable crops,” says Dart. “And they’re wanting to understand what nutrients their crop needs and when it needs them, as well as what forms are best for foliar or for soil applications, because they are not the same.”

Applying the right nutrient at the right growth phase of the plant maximizes the value of the nutrient and results in higher-quality yield.
If growers get all Five Rs right, it’s a recipe for success, Dart says. Get any one of them wrong, and you get poor results and waste time and money. It is a missed opportunity that can leave growers vulnerable to a less effective program with poor results if they simply rely on tradition and don’t ask themselves or their agronomist the key questions involved in the Five Rs and Science-Based Nutrition.