Essential Turfgrass Nutrients

Turfgrass requires 17 nutrients for normal growth and development.  This is why soil testing is so important for a properly maintained lawn.  Some nutrients are needed in large amounts, while other nutrients are needed in only minute quantities. Regardless of the amount required, a deficiency of any of these nutrients will limit the growth and development of your grass. This brief article will provide an introduction to these important nutrients and help you to understand their role in your lawn’s health and appearance.

Non-Mineral Nutrients

Carbon (C), Hydrogen (H) and Oxygen (O) contribute to approximately 90% – 95% of turfgrasses dry weight.  These three nutrients are derived from water (H2O) and carbon dioxide ( CO2) from our atmosphere.  Nature takes care of these for us.  It’s the final 5%-10%, the mineral nutrients, that really separate the cream of the crop.

Mineral Macronutrients

These form the bulk of most turfgrass fertilizers.  In addition to the 3 macronutrients listed above, there are 6 mineral macronutrients: Nitrogen (N), Potassium (K), Phosphorus (P), Sulfer (S), Calcium (Ca), and Magnesium (Mg).

Primary Macronutrients

Nitrogen is vital for the production of chlorophyll, the pigment responsible for your lawn’s dark-green (or not so dark-green) color. Plants deficient in nitrogen have light-green to yellow leaves and may appear stunted. Because turfgrass performs best with consistent supplies of nitrogen, controlled-release fertilizers (CRFs) have become a popular choice for turfgrass applications.

Potassium helps grass to overcome drought stress and improves drought tolerance and winter hardiness, by increasing cell-structure integrity.

Phosphorus promotes root formation and growth and is vitally important to aeration-overseeding success.

Secondary Macronutrients

Calcium is important for the healthy development of plant shoots and roots and is often supplemented with liming applications.

Magnesium is a component of chlorophyll. Deficiencies result in yellowing leaves or foliar chlorosis.  Magnesium may also be supplemented with liming applications.

Sulfur is sometimes used to lower soil pH in cases where high pH levels are problematic.  This is rarely an issue in our region.

Mineral Micronutrients

Micronutrient supplementation is rarely required, as the present soil levels are usually sufficient.  Even though they contibute only trace amounts to turfgrasses dry weight, their importance to your turfgrass cannot be understated.

Iron is important in chlorophyll formation and photosynthesis. Deficiencies may result in chlorosis of young leaves. Iron can help to enhance turf color without stimulating excessive leaf growth.

Manganese excess can reduce plant growth or produce brown spots, while deficiency may cause gray or tan spots.

Zinc helps to regulate metabolic activity.

Copper is a component of various plant enzymes, but excess can lead to iron deficiency.

Molybdenum deficiency may cause twisted leaves and marginal scorching.

Boron plays a role in DNA synthesis and translocation of sugars.

Chlorine deficiencies result in wilted leaves that become bronze, then chlorotic, and then necrotic. Excess chlorine can cause salt injury and leaf burn.

Nickel and Cobalt are recently established essential plant nutrients. Nickel promotes seed development and cobalt is used for nitrogen fixation.