Uses for Iron & Zinc on Lawns

Nutrients in Lawns

• There are two distinct categories of plant nutrients: macronutrients like nitrogen, phosphorus and potassium and micronutrients such as zinc and iron. Macronutrients play a decidedly more important role in plant health, but make no mistake that deficiencies in micronutrients can have potentially serious health effects in your lawn. Plants need larger amounts of macronutrients to grow healthily; micronutrients are only considered apart from macronutrients because, even though they play just as critical role in plant development, plants require much smaller amount of macronutrients.

Zinc and Iron in Lawns

• Zinc and iron play vital roles in lawn plant health. The shallow root systems of most species of grass require zinc and iron to be able to absorb sufficient nutrients from surrounding soil. Zinc plays a vital role in creating the deep, green color that so many homeowners covet in their lawns. If the soil in which a grass is growing has too much of one or more of the macronutrients such as phosphorus, the grass's ability to uptake zinc and iron is negatively affected, a fact that underscores the interdependent relationship of macronutrients and micronutrients in grass growth.

Zinc and Iron Deficiencies

• One way to avoid problems associated with zinc and iron deficiencies in lawn grass is to recognize the symptoms of these deficiencies. Zinc deficiencies are evidenced by a plant's tissue taking on a bleached appearance and overall stunted growth. Again, because the availability of nutrients both micro and macro are so interdependent, a zinc or iron deficiency can lead to other growth symptoms caused by a deficiency in macronutrients. These symptoms include diminished new growth, brown patches and an overall reduction in lawn vigor.

Supplementing Zinc and Iron

• Supplementing iron and zinc to lawn grasses can be somewhat difficult because applying zinc and iron formulations directly to the plants themselves can often do more harm than good. Iron and zinc applied directly to soil is quickly bound up by soil particles, particularly in alkaline soils, and is made unavailable to grass roots. Foliar applications of zinc and iron formulations sold in gardening supply stores tend to be much more effective. Texas A&m University's Agrilife Extension recommends applying 0.5 to 1 percent solution of both iron and zinc directly to the top of the lawn and to carefully monitor the grass for growth improvements that indicate zinc and iron have now been restored to ideal levels.