Why fertilize late summer/early fall?
If a lawn has been managed using a complete lawn care program, it has not been fertilized since late spring. By September, the late spring feeding is beginning to wear off, the root system is becoming depleted, and the turf is beginning to enter an important natural growth cycle which we need to take advantage of.
It is during these cooler temperatures, that conditions are optimum for root growth, shoot density, and better winter color retention in terms of turfgrass quality.
When is the right time to fertilize?
Not to be mistaken with the late fall fertilizer application, this application needs to be done after the heat of the summer but before the grass begins to go dormant.
If applied too soon, the grass will use the nitrogen for leafy, top growth rather than building the root system. If applied too late, the grass will be entering dormancy and not take full advantage of the root building characteristics of the application. Try to time the application to coincide with rainfall to ensure the product gets adequately watered in.
How much fertilizer is needed?
Consider this application a “bridge” feeding. The grass should be given just enough fertilizer to restore its energy reserves and make it through the remainder of the season. It is recommended that a feeding of ¾ lb of nitrogen be applied when the night time temperatures begin to fall below 55˚F.
For example, an acceptable fertilizer blend would be 25-0-12 with IBDU. A small amount of nitrogen is immediately available to the plant while the rest is in slow release form, allowing it to slowly break down and provide an extended feeding to the grass.
Late summer/early fall fertilizing should be applied in conjunction with a complete lawn care fertilizer program for best results.