Lawn micronutrients are an often overlooked aspect of fertilization, but many people don’t know that the right micronutrients can pay big dividends in turfgrass health. Nitrogen, potassium, and phosphorus (N-P-K) are the three most traditional macronutrients and are the primary drivers of growth and health in turfgrass. However, in some soils and pH ranges (particularly high pH sandy soils), micronutrients are often the factor that makes or breaks the outcome of your lawn. When attempting to diagnose turfgrass issues, a soil test should be performed to determine what soil levels, pH levels, and nutrient levels are present. While it’s true that maintaining a healthy lawn is partly art and partly science, without basic data, you’ll find yourself shooting in the dark. Public universities and private labs in every state offer soil testing services for a minimum fee. It’s truly the best money you can spend on your lawn.
Next, let’s dive into each of the primary turf micronutrients, what they do, and how to identify a possible deficiency. Our Lawnifi® fertility program contains all of the necessary elements when it comes to micronutrient health. A bottle of Recover and Maintain, which are included in the fertilizer boxes below, provide micronutrients for lawns. This is just one of the many reasons why our Lawnifi formula has rendered such outstanding results among customers. Learn more in Why Use Lawnifi Fertilizer?.
There are macronutrients and micronutrients when it comes to soil and plant health. As previously explained, macronutrients that are important to soil health include nitrogen, phosphorus, and potassium. Micronutrients are needed in smaller supply but are still just as necessary to overall plant and soil health as macronutrients. A few micronutrients include iron, magnesium, manganese, copper, and sulfur.
Iron (Fe) Iron plays a major role in chlorophyll and is one of the best ways to get the green-up benefits of nitrogen without excessive leaf growth and increased risk of fungus, particularly in wet conditions. An iron deficiency will typically manifest itself through a yellow discoloration also known as chlorosis where the grass doesn’t produce enough chlorophyll. Just a few days after an iron application, a positive green-up response should be evident as chlorophyll is restored. High pH levels, high calcium content, and wet conditions yield the highest chance for an iron deficiency. Soils that are poorly aerated and compacted also have a higher chance of iron deficiency.
Magnesium (Mg) Like iron, a magnesium deficiency will present itself as chlorosis. Instead of the deficiency occurring in high pH or wet clay soils, magnesium deficiency will usually occur in low pH and sandy soils. Magnesium helps fortify turfgrass for winter and plays a key role in producing chlorophyll and processing nitrogen, phosphate, and iron. Beware of over-application though, when unprotected, magnesium can react with calcium and potassium to create nutrient lockup.
Manganese (Mn) Many scientists believe that manganese can help protect plants from disease. It also helps plants ingest nitrogen and complete the photosynthesis process. A manganese deficiency will typically occur in sandy, high pH soils and will present spotted or patterned discoloration of the leaves. Manganese is most available at a pH of 6, but it is not advised to keep the pH that low for most types of turfgrass.
Copper (Cu) A required element for producing chlorophyll and activating enzymes, copper is an important element for turfgrass health. It also helps to fortify cell well strength. Look for withered leaves, stunted growth, and leaves with a dark almost blue color. Copper deficiency is most likely in sandy soils and high pH levels.
Sulfur (S) To produce nitrogen, plants need sulfur. Additionally, sulfur plays a role in forming proteins. Sulfur deficiency issues used to be very uncommon because of the large amount of sulfur in the air caused by manufacturing and engine emissions. Because of its accumulation in the atmosphere, sulfur was naturally applied to lawns via rainfall. The Clean Air Act changed emissions standards and took a lot of sulfur out of the atmosphere, which is a good thing. While our air is indeed cleaner, turfgrass still needs sulfur. This is why in some cases, sulfur may need to be supplemented. Slow growth and yellowing of leaves are the most common signs of sulfur deficiency.
The complexity of turfgrass and the way plants use various elements to grow is nothing short of amazing. Keeping the right nutrient balance is a sure path to a successful and sustainable lawn. The next time you shop for fertilizer, consider micronutrients beyond the basic N-P-K formula. The results may surprise you! Read the Sod University article on understanding a fertilizer label for more information.