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Lawns come in many variations – dense and lush, thin and weedy, young or decades-old, growing in sandy soil or compacted clay, and growing in open sun vs. shade, to name a few.

Since all lawns aren’t the same, different care regimens are needed for different settings – ideally tailored to what each lawn needs.

When it comes to the sometimes confusing array of lawn fertilizers, selection factors include the nutrients already in the soil, the status of the existing lawn, and the type of grass being grown as well as the level and kind of inputs the lawn-owner wants to invest.

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How to sort it out?

A good starting point is to have the lawn’s soil tested. Do-it-yourself, at-home tests are available to get a general read on the basic nutrients and pH (the soil’s acidity level). But some of the best results come from tests offered through state land-grant universities and their Extension services. Extension offices and many garden centers sell kits, usually for around $10.

Lawn-owners send samples of their soil to the state lab and then receive a report on the soil’s fertilizer needs as well as recommendations on which fertilizer to add and how much.

A second up-front consideration is to identify problems the lawn has been having, such as poor color or growth, disease, or rampant weeds.

Many lawn problems are related to soil nutrition and can give you a clue about specific fertilizer needs. Grass that’s light green or yellow-green rather than dark green is often a sign, for example, that the soil is lacking in nitrogen.

Diseases such as dollar spot, rust, and red thread tend to occur more in under-fertilized, nitrogen-poor lawns and weeds are often more prevalent in under-fertilized lawns due to weak grass growth.

On the other hand, lawns that are over-fertilized – especially with too much nitrogen – tend to be more prone to diseases such as summer patch, brown patch, and pythium blight as well as more likely to develop excess thatch.

Read more on lawn diseases

Read more on thatch problems in the lawn

Fertilizer Bag Breakdown

Types of Fertilizers

The most important nutrient for turfgrass is nitrogen. It’s the main fuel for blade growth and the production of chlorophyll, which gives grass its rich, green color. You can tell how much nitrogen is in each fertilizer by looking for a three-digit code that’s required on all fertilizer products.

The first number is the percentage of the bag’s weight that contains nitrogen. The second number is the percentage of phosphorus, which is important for root growth and energy production. And the third number is the percent of potassium, which is important for fending off drought, disease, and other stressors.

A code of 20-5-10, for example, tells you that 20 percent of the product’s weight is nitrogen, 5 percent is phosphorous, and 10 percent is potassium.

Different fertilizers contain different breakdowns of these three “macronutrients” because they’re tailored to different kinds of plants and to soils with different nutrient levels. Since lawns are such heavy nitrogen users, most lawn fertilizers are highest in nitrogen – often at 20 percent or more.

Most soils already have sufficient phosphorus for good grass growth, so to prevent waste and potential pollution from runoff, almost all GreenView lawn fertilizers contain no phosphorus.

And since potassium aids a lawn’s winter hardiness in cool climates, it’s a key ingredient in fall lawn fertilizers.

How much and how often should I fertilize?

Up until recently, most lawn-care programs recommended fertilizing four or more times a year since most of the added nitrogen was depleted in about eight weeks.

But with the arrival of coated granules and other “slow-release” nitrogen technology, lawns can be fertilized less often with longer and more paced effects.

GreenView’s Fairway Formula lawn fertilizers, for example, use a patented formulation of slow-release nitrogen to feed over 12 weeks, achieving good results with just two fertilizer applications per year.

Besides being a labor-saver, these fertilizers virtually eliminate the possibility of burning lawns from applying too much traditional “fast-release” nitrogen.

GreenView Fairway Formula fertilizers are typically applied once in spring and once in fall.  

GreenView Fairway Formula

GreenView Fairway Formula spring options include:

The fall treatment, ideally done in September or October, uses Fairway Formula Fall Fertilizer, a higher-potassium 30-0-12 formula that repairs summer damage and encourages winter survival and quick spring green-up.

For those leaning organic, GreenView has a slow-acting, 15-0-7, organics-rich fertilizer called Turf Nurture that can be used just once or twice per year.

And for those starting new lawns, GreenView Starter Fertilizer with GreenSmart is an option that includes phosphorus to encourage early rooting along with 10 percent each of nitrogen and potassium.

Fertilizing tips

  • Check the label for the type of spreader you’re using to make sure you apply the right amount.
  • Check the package for advice on spreading the granules evenly and without overlapping or over-applying.
  • To get the nutrients working as soon as possible, water the lawn a day or two before applying fertilizer and then water well immediately afterward. Or plan to fertilize just before rain is forecast. (The exception is fertilizers that contain weed-killers, which are best applied to damp lawns that are then not watered for at least 24 hours after application.)
  • Never fertilize while the lawn is frozen, dormant in the summer heat, or under drought stress.
  • Be aware that some regions have restrictions on when you can fertilize lawns and under which conditions phosphorus is allowed.