Stop the yellow: When and how to apply iron for greener lawns, trees, and gardens

If your trees or lawn start the season looking more lemon than lime, you may be seeing iron chlorosis—a common nutrient problem across much of the west. It’s especially noticeable in early spring, when new leaves emerge pale yellow, but the veins stay dark green. While the symptoms may look like a fertilizer deficiency, the real problem isn’t always a lack of iron in the soil. More often, it’s that the iron already present has become unavailable to plants because of our region’s high-pH, alkaline soils.

You might say, my trees and shrubs have already lost their leaves, and my grass is going to sleep for the year—why worry about this now? The answer is that fall and early spring are the best times to correct the problem before it shows up again next growing season. With a little planning n