7/2/2013 - By Harrell's

Fall Fertilization is the MOST IMPORTANT application of the year.

I can hear many of you saying “what?”.  Yes, if you could only fertilize a lawn once per year, fall would be or should be the time you choose to apply your fertilizer.  Why?  The reason is that during the fall of the year, turfgrasses (both cool- and warm-season) fix carbohydrates or food reserves in their roots.  The proper timing of this application should be when the ambient temperatures are cooling down and clipping yields are low.

Ideally, the timing for this application is when the turfgrass shoot growth (leaves) are minimal, yet the roots are still actively growing.  The best way to approach this fall fertilization is to apply a slow release fertilizer blend that contains at least 70% of its nitrogen from XCU or a polymer sulfur coated urea product.  This will release nitrogen over a 6-week period after application and this will guarantee that you have nitrogen releasing and available to the turfgrass plants to allow it to fix carbohydrates (CHOs).

Many lawn care operators will apply a soluble nitrogen source such as ammonium sulfate or urea for this application, but it will only release nitrogen for a week or two (maximum) and will not be as efficient as building up CHO reserves in the plant.  So, get up from your computer and go apply some fertilizer to insure a healthy turfgrass plant next spring!