Lawn Care Questions
When is the best time of year to apply fertilizer? Can a weed and feed product work in the fall? What should be the primary ingredient in fall fertilizer? What are the best ways to treat brown patch fungus? Do I need to treat the entire yard or just the brown areas?
Carroll County Maryland
Late summer into the fall is the recommended time to apply fertilizer to cool-season grass like tall fescue. Perform a soil test to check phosphorus levels and pH. https://extension.umd.edu/hgic/topics/soil-testing
Lawn fertilizers now sold in the state are formulated to comply with lawn fertilizer law. Lawn maintenance fertilizers have zero phosphorus in them and contain at least 20% slow-release nitrogen. The primary nutrient is nitrogen. Specialty products containing phosphorus are still available and may be used when a soil test indicates the need for phosphorus.
Follow University of Maryland Extension lawn fertilizer schedule for timing and amount of nitrogen. https://extension.umd.edu/hgic/topics/ume-lawn-fertilizer-schedule-home-lawns
You did not mention the weeds you are trying to control. A fall weed and feed can work on winter annuals like chickweed. You will have to look on the label to see what weeds are listed. If you put down a weed and feed, you will be be able to seed.
Here is our page on brown patch and management. https://extension.umd.edu/hgic/topics/brown-patch-lawns