Iron May Be the Key to a Green Lawn
In our lawn obsessed culture, homeowners are conditioned to pile on fertilizers high in nitrogen. Soils and grasses have varying abilities to deal with all that nitrogen, however, and all sorts of factors may limit how green your lawn can become. The pH can be too high, or too low. The soil may be overly compacted, or the grass can be genetically predisposed to be light green.
For the ultimate green color of a particular grass plant, the goal is to create an environment for most efficient photosynthesis. One key may well be the amount of available iron. Although iron is not part of chlorophyll, iron is essential for chlorophyll synthesis. Lawns yellowish in color may be suffering from iron chlorosis — which can ultimately be lethal to plants in really severe cases.
Lawns can also be suffering from too much iron, in which case the turf will appear a goulish gray color. This is rare, however, unless someone has applied too much iron as a soil amendment.
The safest way to know for certain that your lawn is lacking in iron is by obtaining a soil test from the local Cooperative Extension Service at the state university, or from a qualified lab. Be sure to tell the lab that you’re growing grass and that you want the “plant available” iron to be measured.
Several organic lawn product manufacturers include iron in their blends. Greening a lawn through the application of iron rather than excessive nitrogen is generally better for the soil and grass, which will not grow faster, yet appear healthier. Milorganite includes iron, along with nitrogen and phosphorus, in its product that has been favored by the golf course industry for decades. I recently helped create an educational video for Natural Industries, which manufactures a product known as Actino-IRON — a soil fungicide and iron amendment all in one: http://www.youtube.com/user/naturalindustries?feature=mhum. If you live in a region where these soil-borne diseases are prevalent, this can be an excellent product to help you save your lawn and avoid toxic fungicides.