Fall lawn fertilizing can be done any time from the first part of October up until mid November in Iowa lawns.  There are several things to consider when timing a fall lawn fertilizing application.  The first thing to consider is leaves.  It is best to get your fall lawn fertilizing application done before the leaves start to fall or when they are mostly gone from your lawn.  It will not hurt to apply fertilizer if leaves are present on your lawn.  The reason why we recommend working around the leaves is to avoid a misapplication.  A misapplication can happen when the leaves are so thick that the granular fertilizer is deflected off the surface of the grass.  This can cause more fertilizer in some areas and less in others.  What you want in a fall lawn fertilizing application is uniformity.  A uniform application will apply the same rate of product on the entire lawn.  If your lawn has minimal trees or minimal leaves, then feel free to apply lawn fertilizer at anytime in the fall.

Fall Lawn Fertilizing

Fall lawn fertilizing hurdles to avoid.

Fertilizing too early in the fall can reduce the effectiveness of the fall lawn fertilizing application.  In the fall we usually receive more rain than in the summer.  More rain, means faster break-down of your granular fertilizer.  If you apply too early, your fertilizer may be consumed or already broken down by the end of fall.  The purpose of a fall lawn fertilizing application is to provide nutrients to the grass that it can use over the course of the winter.  Another pit fall to watch out for is fertilizing when the ground is already frozen.  If the ground is frozen, fertilizer cannot be broken down to reach the root system of the grass.  The fertilizer will most likely not be used until the following spring.