Kentucky blue grass is the most popular cool-season turfgrass used in lawns where winters are colder. Kentucky blue grass creates a lush-looking, bluish-green lawn that can tolerate extreme freezing weather in winter and heavier foot traffic. This grass type requires some extra watering during the summer, however, because it will enter a dormant state during droughts or high heat. Kentucky blue grass is a moderate to fine-textured grass that grows best in sunny lawns.
Water your Kentucky blue grass once every week from spring until fall in the absence of rainfall, applying ¾ inch to 1 inch of water. Try to wet the top 6 to 8 inches of soil in order to provide adequate moisture to the grass roots.
Mow your Kentucky blue grass lawn once or twice per week from spring until fall to maintain a grass height of 1 ½ to 2 ¼ inches. Avoid cutting more than one-third of the grass's total height in a single mowing.
Feed your Kentucky blue grass lawn each year with a 16-4-8 NPK fertilizer, at a rate of 3 to 5 pounds of nitrogen per 1,000 square feet of lawn. Divide the fertilizer into three or four equal applications, with one application in the spring, another six weeks later, again in early fall and once more in late fall.
Treat your Kentucky blue grass for iron chlorosis, which is due to over-fertilizing with too much phosphorous and causes the grass to yellow. Correct iron chlorosis by selecting a fertilizer that contains a lower amount of phosphorous and apply an additional feeding of ferrous sulfate to the grass at the recommended dosage on the label.