Kentucky bluegrass, known botanically as Poa pratensis, is a cool-season grass prized for its tall blades and deep greenish blue hue. It is grown as an ornamental or field grass and as a shorn turf grass. Like many turf grasses, Kentucky bluegrass grows into a dense and lush lawn with ample fertilization and water.
Fertilize new Kentucky bluegrass lawns less than a year old with between 5 and 6 lbs. of nitrogen-rich lawn fertilizer for every 1,000 square feet of lawn. Spread this out over multiple applications from spring through fall so that you are never laying down more than 1 lb. of fertilizer per 1,000 square feet in any one session.
Scale back fertilizer application rates in the second and third years and each year thereafter to between just 2 and 3 lbs. of lawn fertilizer for every 1,000 square feet.
Fill a drop spreader with the appropriate amount of fertilizer for the area. Set the spreader rate dial to the number recommended on the lawn fertilizer label. Start at one edge of your Kentucky bluegrass lawn and walk at a steady pace with the dropper engaged. Disengage the drop mechanism while executing turns and overlap each pass just slightly to ensure even coverage over the lawn.
Water the lawn well until drenched but so that there is no runoff or standing water after applying the fertilizer. This will wash the granules down to the thatch and dissolve the nutrients in the root zone where they can go to work to feed the lawn.
Spray your Bluegrass lawn with an iron sulfate product if needed to combat iron chlorosis and the yellowing of grass blades common when growing Bluegrass on alkaline soil. Apply the spray to the grass blades according to the product label directions but not to exceed 2 oz. of product for every 1,000 square feet of lawn expanse. Repeat as needed in keeping with the dosing guidelines.