A fertile debate

Lawn care operators have a number of items to consider when choosing between a granular or liquid fertilizer program.

Here is a look at some of the pros and cons of granular and liquid fertilizer in lawn treatments from two lawn care professionals who are in charge of selecting and applying lawn care products for residential and commercial properties in some of the larger markets in the country.

Granular.

Tom Knopsnyder, vice president of operations with Green Lawn Fertilizing/Green Pest Solutions in West Chester, Pennsylvania, says the company is sold on using granular fertilizer for most of the properties they service – 85 percent residential and 15 percent commercial.

He says the granular slow release fertilizers stay in the soil for a longer period of time than do the liquid applications. Another plus for granular is the perception of property owners.

“Customers seem to like the granular more because they can see it and they’re used to going to Home Depot and buying a granular product,” Knopsnyder says. “With liquid, it looks like they’re just spraying these chemicals everywhere.”

The math is also a little less complicated with granular products, says Dr. Rodney St. John of Ryan Lawn & Tree, out of Overland Park, Kansas. St. John, who is an agronomist and a former professor at Kansas State University and now holds the title of vice president, director of agronomy and environmental stewardship at Ryan.

“It’s easy to do the math with granular,” St. John says. “You know so many pounds covers so many square feet – with liquid the math is a little more complicated.” St. John says one of his jobs is to prepare the recommended amount of fertilizer for the crews who will be doing the actual applications.

“The main benefit is the release time; liquid only lasts for a few weeks, where granular will last up to 16 weeks, depending on the type of poly coated fertilizer we use,” he says.

One drawback St. John sees in granular fertilizer is with the mechanized equipment they use. He says the operator can get going pretty fast or cut corners, which reduces the amount of product that is applied.

Another drawback of granular fertilizers, according to both lawn care professionals, is the clean up that is often required after application. Pelleted fertilizer often inadvertently lands on sidewalks, driveways and streets.

Liquid.

One of the biggest advantages of using a liquid application is you can mix products like fungicides and herbicides with fertilizer into a tank, and take care of everything at once.

“Some herbicides that are available as a liquid aren’t available in a granular,” says St. John.

Both companies find occasions where it is more practical to use a liquid fertilizer over a granular. St. John says it’s easier to pull a hose up a steep hill and fertilize with a liquid then it is to drive equipment up a sloping property.

And, of course, different products, like fungicides and herbicides, can be mixed in with liquid fertilizers as needed.

Some companies also use liquid applications in the spring for a quick green up and then follow up with granular applications.

Knopsnyder says one disadvantage of liquid applications goes back to customer perception. A customer can see that the job got done because they can easily see that someone has been treading on their lawn with a spreader while the footprints of someone walking with a hose is less discernable.

St. John adds that liquid fertilizers can be sticky and messy and even stain clothing.

The author is a freelance writer based in Michigan.