second on corn gluten meal. Applying in fall will act also to prevent germination of crabgrass and dandelions. A generous coating of organic or good yard waste (low on wood products)
compost is a gentle way to feed your lawn in the fall. Here in CO, your lawn should be starting to brown out with this heat. bluegrass and rye are cool season grasses. Continue to water them deeply, and less often than most people. They will green up again in the fall when the daytime temps break back to the 80s. That is also a premiuim time to reseed. Chemical fertilizers can set the stage for other problems like mold, fungus and some weeds. theyre really just salts. Try the corn gluten, or blood meal if you want to apply nitrogen.