Of all the chemical applications to turf, fertilizer is by far the most common. Despite this, it’s often the least customized. With herbicides, you follow the label or run the risk of seriously damaging turf. But with modern slow-release fertilizers, many turf managers use a common equation, often not taking into consideration the detailed characteristics that could boost turf color and vigor from good to great.
Take a good look
Fertilizer nourishes turf, making it healthy. The healthier the turf, the better it can fend off disease and tolerate everyday stresses such as drought, heat and traffic. But too much or too little fertilizer and, instead, you sacrifice the health and resistance you’re trying to promote. Too much fertilizer can lead to foliar burning and actually stimulate disease, insect and weed activity. Too little fertilizer and the lawn won’t thrive, again making it more susceptible to disease, insects and weeds.
To achieve optimal results it’s worth the effort to customize a fertilizer program for turf. This includes analyzing several factors that can impact the timing and amount of fertilizer turf needs to attain that healthy, lush look. In all, there are at least 18 elements that plants require for proper growth; fortunately, they get most of these via natural soil processes. But three of these: nitrogen, phosphorus and potassium (N-P-K), are the critical ones that plants need in large quantities, which is why fertilizer products focus on these three.
As you begin to develop a fertilizer regimen for your client, run through this checklist to help define requirements.
Soil type. If soil is loamy, it will require less fertilizer than one that is sandy or a clay soil. Common sense, yes; but the point is you must know what kind of soil you’re working with. If not, you won’t get the results you and your client expect. Also, soil pH will dictate the amount of phosphorus and potassium you need, so it is important to get soil tested so you know its pH. Soil tests are inexpensive and should be conducted every year or two.
Established or new lawn. Typically, an established lawn is going to require less fertilizer than a new one. The exceptions, of course, are those instances where you are working to improve a thin lawn and increase density, which will call for more fertilizer during the year.
Turf species. Some species, such as Kentucky bluegrass, Bermudagrass, zoysia, and perennial ryegrass need more fertilizer. Other species, such as centipede and tall fescue, can get by with less.
Location. The longer the growing season, the more fertilizer turf will need. So if you’re in a warmer climate, you’ll need to boost fertilizer applications. Typically, this will translate into at least one more application during the year compared with what operators up North are doing.
Weather. The more it rains, the more turf grows and the more fertilizer it needs. Simple as that. So while you may be planning only a few applications of fertilizer this year, you need to be adaptable if the spring and summer are especially rainy. If it’s drier than normal, you should also reassess the turf’s needs and consider cutting back.