1) The lowest rate I could go with and not get a speckled appearance was .4#N/M
2) Granular fertilizer always gets thrown in places you don't want it no mater how carful you are.
3) Granular fertilizers cause a flush of growth for a week or two after application creating a need for extra mowing.
Spraying at a rate of 0.9gpm I can cover 7.7 Acres with one tank. Five tanks covers my fairways and Approaches. I can spray these areas in one day now; where as before it would take me 3 days with the old smaller sprayer.
Another benefit of spraying is my ability to add the growth regulator Paclobutrazol to the tank. This product provide vertical growth regulation and suppresses poa annua growth more than the other grasses. Our low mow bluegrass and fine fescue plants now have a competitive advantage over poa. I am also adding Ferrous Sulfate to the tank for a quicker green up and as another poa irritant.
The products used to spray fairways are:
Blade Fe (15-0-0)
Total cost to spray all fairway is $1500
Total cost to use a granular product on fairways is $1600
A more accurate application with the benefit of a growth regulator for basically the same price.
Two applications in and I am very pleased with the results so far this season.