Department of Agronomy, AY-43-W

PURDUE UNIVERSITY
COOPERATIVE EXTENSION SERVICE
WEST LAFAYETTE, INDIANA


GOLF COURSE FERTILIZATION

Zachary Reicher, Clark Throssell, and Jeff Lefton
Purdue University

Cool-season turfgrasses are the dominant grass species used on Indiana golf courses. These species include Kentucky bluegrass, annual bluegrass, perennial ryegrass, tall fescue, fine fescue, and creeping bentgrass. Cool- season turfgrasses benefit enormously from late fall fertilization programs. Some spring nitrogen applications are recommended, but are usually kept to a minimum.

Warm season grasses such as zoysia and bermudagrass are common in southern Indiana. These species benefit from summer applications of nitrogen.

Before designing a fertilization program for your golf course, soil tests should be taken of greens, tees, and fairways. A soil test is instrumental in determining phosphorus and potassium recommendations and also will identify pH problems. Refer to AY-18, "How to Interpret Your Lawn Soil Test Results".

Fairways

The recommendations listed here are of a general nature; they will be affected by soil type, irrigation practices, and clipping removal. Even so, some practices are common to all. Most fairways are fertilized one to three times per year with a soluble nitrogen fertilizer or one that has at least 1/3, or less, water insoluble nitrogen(WIN). These fertilizers provide quickly available nitrogen at a relatively low cost. The optimum nitrogen application recommendations are:

 Actual N

Datelbs/1000

lbs/A

September1.043
Nov. 1 - Nov. 15* 1.0-1.543-65
May 15 - June 11.043

* Apply after last mowing but while grass is still green

Often budgets do not allow for this amount of nitrogen to be applied. If only one application can be made, apply the September treatment. If two applications can be made, apply the September and November treatments.

November fertilizer applications should be of fertilizer that contains 70% or more water soluble nitrogen or a nitrogen source containing isobutyldene diurea(IBDU). This is because the cool fall temperatures reduce microbial activity needed to release nitrogen from ureaformaldehyde(UF) fertilizers, sulfur coated urea(SCU), or natural organic nitrogen sources.

Advantages of the late fall fertilization include a denser turf which reduces weed competition, improved root systems, reduced mowing frequency in the spring, earlier spring greenup, better drought tolerance, and fewer disease problems.

Greens

Putting greens will respond to fertilizer in the same way as fairways respond to fertilizer but recommendations are more complicated. Fertilizer recomendations will be affected by soil texture, irrigation practices, bentgrass cultivar, age of green, mowing height, traffic, desired putting speed, and tournament schedule. The following plan can be used as a guide:


Datelbs N/1000ft2

August0. 5
September1.0
November1.5
May0.5
June0.5

This plan, or program, is for fertilizers containing more than 1/3 WIN. Avoid using fertilizers containing less than 1/3 WIN (thereby avoiding buildup of slow release nitrogen in the green). This program should be used as a guide only. Nevertheless, experience of the greens superintendent will determine the final fertilizer applications. As a rule of thumb, color and growth dictate fertilizer needs. If greens are off-color, or are not growing fast enough to recover from wear during the summer, 0.5 lbs. N/1000 ft2 should correct the problem without a large growth flush. Dark green, lush turf should be avoided during the summer because of increased susceptibility to pythium, brown patch, and other diseases. Some superintendents employ a "spoon feeding" program during the summer by applying frequent applications of 1/8 lb N, or less, every other week. This allows maximum control over bentgrass growth.

Tees

Total nitrogen applied for tees should be between that of greens and that of fairways. One can use the recommendations for greens and reduce the amount of nitrogen to fit your needs. All of the factors that affect the fertilizer used for greens are the same for tees. However, par 3 tees may need more fertilizer to recover from divots.

Roughs

Roughs are rarely fertilized because of added maintenance costs. One lb N/1000 ft2 applied in September is sufficient for golf course roughs.


Cooperative Extension Work in Agriculture and Home Economics, State of Indiana, Purdue University and U.S. Department of Agriculture Cooperating. H.A. Wadsworth, Director, West Lafayette, IN. Issued in furtherance of the Acts of May 8 and June 30, 1914. It is the policy of the Cooperative Extension Service of Purdue University that all persons shall have equal opportunity and access to our programs and facilities.