Garden Column for the Salisbury Post

Darrell Blackwelder

February 17, 2005

Judging by the bags of fertilizer I’ve seen at local garden stores, spring lawn fertilization is just around the corner. Early spring is the correct time to get lawns into shape before summer.  Poor fertility is a major cause of declining lawns. Too much shade, soil compaction due to foot traffic and excessive weed growth also contribute to thinning or poor turf stands.
    Maximum root establishment is essential for development of thick, healthy fescue lawns. Thin lawns and root growth are often a result of low phosphorus. This is a common problem for new construction where grading has removes the top layer of soil containing valuable phosphorus.
    Those that want to seed their lawn as a total makeover should consider waiting until fall if possible. Cool season fescue lawns are typically easier to establish in the cool weather in September. Lawn establishment in the spring and summer is difficult, but is possible if the weather cooperates.
    Normally, core aeration is done only in the fall, however if lawns are extremely weak or non-existent it is often the best method of placing fertilizer into the root zone. Coring allows fertilizer and seed to penetrate without plowing.
Soil sampling is the best method to determine soil fertility. Unfortunately, it normally takes about 4-6 weeks to receive a sample back from the North Carolina Department of Agriculture-too late for some, but still relevant endeavor for those wanting to improve their lawn.
    Fertilization in the spring can be somewhat tricky because most tend to over fertilize. Only one pound of actual nitrogen should be used in the spring. Slow release, premium fertilizers, is generally recommended because they slowly release fertilizer over a long period of time. Slowly release fertilizer blends usually contain a small amount of grade fertilizer that allows cool season fescue lawns to green quickly, with the balance of the nutrients slowly metered over the short spring growing season.

    Another problem associated with spring fertilization is over liming. Continual liming every year may cause actually decrease nutrient availability of some key nutrients. In most instances, liming should only be done every two to three years.