JOHN CRETTI'S LAWN TIPS
April 2020
Gearing Up for Spring Lawn Care
John Cretti-Horticulturist “Gardening with an Altitude”
Most lawns in Colorado and the Rocky Mountain region are cool season grasses including bluegrass, turf fescue, and perennial rye grasses. Healthy and thriving lawns begin with a good foundation --- healthy and thriving soil. The proper balance of air, water, nutrients will encourage the roots to grow deeply and vigorously.
Before sodding a new lawn, prepare the soil and reap the benefits. A simple way to improve your soil is through the application of organic amendments. As soil structure is improved the soil becomes healthy and can support root growth. A good source of organic matter will break up the heavy, clay-textured soils, as well as improving the water-holding capacity of sandy, and granite-based soils.
Quality organic amendments also buffer the soil, which helps unlock mineral elements so they are available to the plants and helps speed up the formation of a living and healthy soil.
Seeding a new lawn is more time consuming and takes much patience and care. Please refer to my book, Rocky Mountain Getting Started Garden Guide, for details on when and how to seed a lawn.
A neglected lawn's recovery should start with a good core aeration. Proper aeration removes cores of soil and thatch (that water-repellent layer of living and dead roots, stems and leaves that accumulate above the soil surface). Insects, diseases and some weed species find thatch an ideal place to live.
It is particularly important to core aerate lawns that are established on clay soils that are prone to compacting from human and pet traffic, and running the lawn mower over the lawn.
Aeration will increase water and air penetration, stimulate new root growth into the root zone area and provide openings for fertilizer and pulverized compost to enter the soil. If you need to overseed a thin lawn, the openings left from aeration provide lodging places for grass seed to germinate more successfully.
Older lawns with thatch accumulations over one-half inch will benefit from soil aerification. Aeration helps to break through the thatch layers and allows for microbial activity to continue the decomposition of thatch.
The best results can be obtained from aerators that remove 3-inch cores, 3/4-inches in diameter and spaced at 3 to 6 inch intervals. The aerator should cross the lawn at least twice, going in two different directions.
Plugs left from aeration can be unsightly and tracked indoors if left on the surface. If you have time (or have someone to do it for you) rake plugs after aeration and recycle then in the compost pile. If you prefer, you can leave the plugs on the lawn and they will eventually break down after several mowings. Just remember to sharpen the lawn mower blade regularly as mowing plugs will dull the blade.
Fertilizer
After a complete lawn aeration is one of the best times to apply your first application of lawn food. Use a formula for our region that contains nitrogen, phosphorus, and potassium Read and follow label directions for rates and application methods.
Crabgrass Control
If you have a thin, weak lawn that is prone to crabgrass invasion, early- to mid-April is the time to apply a
pre-emergence herbicide. A good pre-emergent control should be used to achieve the longest residual in preventing this invader. Read the label carefully for the actual percentage of active ingredients to control specific weeds that invade your lawn.
For more detailed information on gardening in our unique region, please refer to my books on Rocky Mountain Gardening (Cool Springs Press). Available at your favorite garden store or via Amazon.com.
