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View Full Version : Fertilizer - liquid or granular


dbsoccer
08-22-2008, 04:44 PM
Is there any consensus around using liquid or granular fertilizer on sports turf? I see granular used on large commericial applications but liquid being used on soccer/football fields. Any ideas why they'd be different?

foreplease
08-23-2008, 12:41 AM
I prefer granular fertilizers but have used both.

My take on it is that it takes a much more skilled applicator and more expensive equipment to put down liquids well over large areas. Liquid applications are probably better for precise applications where immediate results are wanted on fine turf (golf tees, greens, fairways) and where having granular fertilizer particles left on the surface for even one day might be objectionable. Small frequent applications are the norm for liquid fertilizers. The term "spoon feeding" is often used to describe their use.

The chance of burning the grass is higher with sprayed forms of nitrogen. Applying liquid fertilizers without having an irrigation system is inviting disaster. Atmospheric loss (volatility) is greater with liquid applications. They are short lived gone entirely in as little as two weeks on sandy soils. Some small benefit could be seen as late as four weeks after application but is not likely or significant.

Generally, it is not possible or practical (or desirable) to apply much nitrogen at one time using liquids. I do not have a lot of experience with liquids. Rates I have used range from 0.1 to 0.4 # N/M. With granular products, I would not make an application on an athletic field at less than 0.5 # N/M and almost all of mine are between 0.75 – 1.25, depending on product, time of year, budget for the field, weather, and some sense of how the field has responded in the past or what its current versus desired condition is. Some component of typical granular fertilizers is coated (sulphur, poly) to extend release of part of the total nitrogen over 14-18 weeks, or more.

Broadcast applications with granular products are more forgiving in terms of overlapping. Liquids are not convenient for me because I have my sprayer calibrated at near one-half gallon per M whereas it takes a much higher volume of water to move some of the product into root zone. At lower volumes of water, liquid applications are just high-risk foliar applications.

Neither product is all good or all bad. This is my opinion and approach. Others undoubtedly have great success with liquids and/or approaches quite different than mine.