Lawn banana: potassium (K)

Potassium (K) is the last number in the triple letter fertilizer designation you find on the bag; 0-0-62 or N-P-K.  Potassium is a salty fertilizer which is generally applied in the fall to enhance turf performance the following year.  Second only to nitrogen in importance, potassium helps regulate water movement inside the grass plant which is critical during droughts like this past summer.
K also plays a key role in thickening cell walls to improve winter hardiness against the cold.  In terms of the next growing season, potassium improves wear tolerance in your lawn which comes in handy after a big party, BBQ, or soccer practice.  Although research is inconclusive, some disease resistance may be gained with not only a proper amount of potassium in the soil, but a balance with other key nutrients.  While no one nutrient is the “end all”, magic bullet; there are clear benefits to having a pure potassium treatment applied in the late fall before dormancy for improved water regulation, winter hardiness and wear tolerance.
I have applied potassium fertilizer to lawns and had the most spectacular, vivid green-up the following spring; the lawn almost seemed to glow!  I can speak from experience that ending the year with a banana for your lawn can help set the stage for a great April and May.  Since potassium is a small granule either white or reddish in tint, the product can easily be applied over a moderate leaf cover without reducing results.  Remember, with an analysis of 0-0-62 or 0-0-60 you have a high amount of potassium but no nitrogen or phosphorus.  With this special type of fertilizer, you only need a small amount of potassium fertilizer to receive great results next spring.