In order for a lawn to thrive it needs a healthy medium (the soil) to grow in. An organic fertilization program focuses on the soil’s quality. The aim is to nurture the soil and the soil food web in addition to feeding the plant.
The soil food web refers to the multitude of life forms in the soil. These forms range in size and kind from microscopic one-celled bacteria, algae, fungi, and protozoa, to larger nematodes, anthropods, earthworms, insects, plant roots, and small animals.
They help break down organic matter, aerate the soil, prey on unwanted pests and make nutrients available to the grass. The relatively few pests that create problems in landscape are less likely to dominate a system that is also home to their predators.
Chemical fertilizers and pesticides act as irritants to many of these beneficial life forms, killing them or causing them to flee the areas. This has an adverse affect on the health of the soil. The grass becomes dependent on the chemicals to grow rather than getting its nutrients from the soil. On properties that have been routinely treated with chemicals the soil will likely be compacted and thatch built up. This may result in the need for extra patience while beneficial life forms return.
These beneficial organisms can transform compacted soil into a soft porous medium. This soft porous soil is beneficial to the grass because it will have improved water retention characteristics, oxygen holding capacity and nutrient holding capability. It will also be permeable so that grass roots can more easily penetrate it, encouraging deeper, stronger roots.
While your soil is being improved and encouraging beneficial life forms to return there are a number of cultural practices that can be started immediately to create a healthy, sustainable lawn.