Key Steps Heading into the Spring

Newsletter, February 2020

The spring transitional period is a tough time for managing turfgrass, especially when we have some sporadic cool fronts. The warming periods cause the grass to green up. However, the light intensity is still low, which reduces the plant’s ability to fully function physiologically.

Although we cannot control or even predict weather conditions, there are 2 key steps you can take to a successful transition to spring that will set your turfgrass off to a great start for thriving during the warm, high-traffic months:

1. Monitor growing degree days (GDD). This will help you get a good indication of growth potential. Having a deep understanding of growth potential is fundamental for determining when to start nutrient inputs, herbicides and plant protection applications.

GDD = average daily temp 0F (max high + min low) / (2 - base temp 500F*)

(*22 & 32 used for northern climates)

GDD is a calculation of accumulated heat to help predict different plant physiological responses. Turf typically starts actively growing between 200 – 300 GDD, which is when nutrient applications should be considered.

2. Plan your fertility program ahead of time, based on the most recent data from soil and tissue analysis for precise nutritional needs.

Phosphorus (P), calcium (Ca) and iron (Fe) are fundamental nutrients in the spring for promoting plant health and may be restricted due to soil variability, deficient concentrations, less than desired temperatures, and low transpiration rates. These nutrients tend to be neglected, especially when soil tests show adequate amounts. It is important to have in mind the role they play in turf nutrition:

• Phosphorus – P will improve turf health by promoting root development and establishment and supporting all physiological processes needed to enhance growth and recuperative potential. P is immobile in the soil so choosing a source that is readily available to the plant is essential.
• Calcium – Ca is a key nutrient for cell wall strength and assists in protecting new plant tissue. Remember, not all sources of calcium are soluble and only soluble Ca is immediately available for plant uptake.
• Iron – Fe is essential for chlorophyll formation, increasing color and shoot growth, and for promoting photosynthesis. Fe can be precipitated out of the soil solution, becoming unavailable fairly easy.


Choosing the right source, right rate, and right timing to apply these nutrients will promote turf’s health during spring and help sustain high quality turf for customers. Keep navigating our OptimumTurf webpages for additional resources for building nutritional programs.

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Neil Mayberry
Neil Mayberry
Regional Market Development Manager