Lawns should typically be fertilized when they are actively growing. Cool-season grasses such as Kentucky bluegrass, tall fescue and perennial ryegrass benefit from being fertilized in fall and late spring. The fall application is important as it helps the turf build up food reserves enabling it to green up earlier in the spring. Cool-season grasses usually have a flush of growth in mid-spring using up much of the stored energy. By applying fertilizer shortly after this growth, the turf is able to replenish the depleted nutrients ensuring the plants are strong heading into the stress of summer. A slow-release nitrogen fertilizer is best for the May application. Liquid or dry fertilizer are fine, though dry tends to be easier for homeowners to apply.
Warm-season grasses such as bermudagrass, buffalograss and zoysiagrass should be fertilized in late spring and/or summer. (https://bookstore.ksre.ksu.edu/pubs/mf2324.pdf)
Always read the fertilizer label for the correct rate and specific instructions.
- Sweep dry fertilizers off hard surfaces and back onto the lawn to prevent it from washing into storm drains polluting our waterways.
- Water after applying fertilizer if rain is not in immediate forecast.