Garden Column for the
Salisbury Post
Darrell Blackwelder
March 14, 2003
The
turf test plots at the Extension Office are still straw-brown. However, the tops
of lawns throughout Rowan County are slowly turning green underneath. Lawn mower
blades should be sharpened and engines tuned as the mowing season is about to
begin.
Now that the weather has broken, cool season lawns should be
fertilized. Properly fertilized vigorously growing turf withstands summer
droughts, diseases and other pest problems that plague most homeowners.
It is important to test the soil every two to three years to monitor soil pH and
phosphorus levels. Cool season turf grows best at a slightly acid pH of 6.0 to
6.5.
Turf specialists recommend one pound of actual nitrogen to be
applied before May. Nitrogen can be applied in split applications during the
spring. Many homeowners still choose to apply agricultural grade fertilizers
such as 10-10-10, 17-17-17 or 30-0-0. These fertilizers are quick release
fertilizers promoting rapid growth.
Split applications of grade fertilizer now (1/2 pound
nitrogen per 1000 square feet) and again before April are recommend providing
one pound of total nitrogen. Five pounds of 10-10-10 per 1000 square feet
delivers 1/2 pound of actual nitrogen per 1000 square feet of turf, or 215
pounds of 10-10-10 to fertilize per acre of turf.
Excessive rain and rapid uptake quickly deplete nitrogen and
potassium. Late nitrogen applications in late April and May jeopardize healthy
turf by predisposing the turf to brown patch. Brown patch is the fungal disease
that makes huge brown circles in the lawn during late June and July.
Slow release, turf-type fertilizers contain a coated mix of nitrogen and other
elements that slowly release nutrients. Some slow release fertilizers last the
entire growing season, therefore it is best to apply these early. Temperature,
moisture or bacteria trigger the release of the coated nutrients.
Slow release type fertilizers are popular because of the slow
even feeding that produces a deep, green turf without excessive growth. Rapid
growth generated by grade fertilizers promotes extra mowing in the spring. Slow
release fertilizer produces short, even turf growth in the spring.
Another reason to consider slow release turf type fertilizers
is the ease of application with the bags pre-measured to cover 5000 to 10,000
square foot turf areas. Micronutrients or trace elements are standard features
of turf type fertilizers. Trace elements are essential for growth and
development of a lawn.
Over fertilization in the spring is a common mistake made by
homeowners. Applications of one pound of nitrogen per one thousand square feet
in February don't seem like quite enough, but it is an ample supply for good
turf growth. Be very careful in measuring lawns and determining fertilizer
rates.
Fertilization alone does not ensure a beautiful lawn. Weed control, coupled with
proper mowing and pest control contribute much to the beauty of a
lawn.
Cooperative Extension will present information at the Historic Salisbury Foundation's Annual Flower and Garden Show on Sunday, March 16th at 4:00 pm. Darrell Blackwelder will present information on Spring Turf Management, including seeding, fertilization and weed control for cool season lawns. There is a $1.00 admission fee for the program. Call Historic Salisbury at 704-636-0103 for more information.