Grass Maintenance Guide: Understanding Why Grass Turns Yellow and Suggestions for Recovery
Lawns, a common feature in many gardens, can sometimes turn yellow due to various reasons. This article aims to shed light on the common causes of yellowing grass and provide solutions for improving the health of your lawn.
Turf grass rust causes leaves to develop patchy, yellow spots, which can broaden over time, causing the entire leaf to pale. Mowing too low, or scalping, can also cause a lawn to yellow due to the plant's inability to provide enough iron for new growth.
Excessive heat and full sun exposure can lead to heat stress and yellow areas in the lawn. Watering a lawn on an irregular schedule can also cause parts of it to yellow. Overfertilization, on the other hand, can cause an abundance of nitrogen salts, reducing available moisture to grass roots and changing the soil's pH.
Cool season grasses like tall and fine fescues, Kentucky bluegrass, and perennial ryegrass can turn yellow and go dormant in the cold season. Similarly, warm season grasses like Zoysia and St. Augustine have a naturally light green hue, but they can turn tan to yellow during periods of cool temperatures.
Turfgrasses can suffer from iron deficiency, causing a condition called iron chlorosis and yellowing at the top of the turf. An application of iron chelate can help with this issue. Chinch bugs are damaging insects that feed on leaf blades, causing yellowish brown patches in the sod grass. Dog urine can also cause burn spots in the lawn due to its high nitrogen content.
Grubs of Japanese beetles and other beetles can cause lawn discoloration by feeding on grass roots. Soil compaction can interfere with drainage and proper root growth, causing yellowing in the leaf blades.
To prevent or treat yellowing grass blades on compacted lawn areas, it's important to ensure proper soil aeration, adequate watering, balanced fertilization (especially with nitrogen), and avoiding excessive foot traffic to reduce soil compaction. Improving drainage, aerating the lawn, raking up excess grass clippings and fallen leaves, and watering deeply but infrequently can help improve a yellowing lawn.
Thinning out trees and maintaining a sharp mower can help improve the health and vigor of a lawn. Core lawn aeration can increase percolation and air exchange to the roots, improving soil conditions.
Cool season grasses stop active growth in fall to winter, and the change in color is normal for each grass in the associated season. Drought conditions can cause a lawn to turn yellow during the summer. Kentucky bluegrass has a deep green color compared to some other grasses.
In conclusion, understanding the causes of yellowing lawns is crucial in maintaining a healthy and vibrant garden. By addressing these issues and implementing the right solutions, your lawn can regain its green glory.
