When is the best time to apply fall fertilizer to my lawn? I live in Southern Michigan - USDA Zone 6. I have mostly Bluegrass. I've asked several local 'experts' and have gotten responses of mid-sept to late-Oct.
Actually, both are correct and it depends on the health of your lawn. If your lawn's health is so-so and you are trying to improve the quality of the lawn, early to mid September is best. If, on the other hand, you have a very healthy lawn, you can fertilize in either Sept or October - some professionals will fertilize very healthy lawns at both times. In all cases, make sure the lawn is well watered before you fertilize.