How to Green Up Your Lawn with Iron Supplement

If you’ve ever wondered how your neighbor gets such a dark green lawn, the answer just might be iron. A favorite secret weapon of lawn care professionals and golf courses, iron supplements help to impart a lush, deep, blue-green color to lawn grasses.

Iron is particularly effective with fescue and bluegrass, helping these grasses stay deep green during the hot summer months without the increased growth (and subsequent water needs) caused by nitrogen fertilizers. Iron also helps control moss and is the active ingredient in products such as Moss Out.

Types of Iron Lawn Supplements

There are two main types of iron supplements:

• Synthetic Iron Fertilizer: Manufactured iron rich fertilizers, such as Ironite, are an inexpensive and fast-acting supplement. They are usually spread as granules, with foliar sprays also available that can produce results within days. The disadvantage of synthetic iron fertilizers is that they can turn your lawn gray if over applied, and if you’re not careful when spreading, they will stain your concrete driveway a rusty-orange.
• Organic Iron Fertilizer: Organic sources of iron, such as Milorganite and greensand, are slower to break down, but the iron is naturally chelated, which makes it more readily absorbed by the plants. Organic iron sources won’t stain your concrete, and they contain other nutrients that naturally build up your soil and lawn.

How to Apply Iron Lawn Supplements

The best time to apply iron to your lawn is in the spring, when temperatures are in the 60s to 70s F. Avoid spraying or applying iron during hot weather. Follow package instructions exactly, to prevent overdosing.

Grasses don’t require a lot of iron, and it’s generally not needed unless your soil test indicates an iron deficiency. If your lawn is yellow, first make sure it’s getting enough water and regular nutrients before trying iron supplements.

Further Information

• What Does Iron Do For Lawns and Grass? (naturalgreenlawn.com)
• How to Treat Iron Deficiency in Plants (article)
• Fertilizer 101 (article)