# When to fertilize your lawn: by grass type and region > When to fertilize cool-season and warm-season lawns, how many feedings extension services suggest, the growth and weather cues to watch, and when to hold off. Canonical: https://lucernel.com/guides/when-to-fertilize-lawn Last updated: 2026-10-06 Type: Guide. Publisher: Lucernel. ## Short answer Fertilize when the grass is actively growing. For cool-season grasses such as Kentucky bluegrass and fescue, Penn State names late summer (early to mid-September) as the most important feeding, plus late fall and mid- to late spring. Warm-season grasses such as bermudagrass are fed in the growing season after full spring green-up. Skip dormancy, midsummer heat and drought, and days when heavy rain is coming. - **Choose this if:** A calendar reminder works if you have one grass type and your region’s extension dates in hand. - **Choose the other option if:** Lawnzo helps when you want the season planned for your grass and each job checked against the forecast, with what you applied kept in a journal. ## Side by side | | Calendar reminder | Lawnzo | | --- | --- | --- | | Reminds you on a set date | Yes | Yes, from a seasonal plan | | Plan built for your grass type | No, you pick the dates | Yes, from your grass, sun and irrigation | | Checks the forecast for rain and heat | No | Yes, keeps, delays or skips a task and shows why | | Knows the product’s rain-free and temperature limits | No | Yes, from the limits you enter from the label | | Keeps a record of what you applied | Partly, a note | Yes, products, quantities, costs and photos | | Replaces a soil test | No | No | ## Fertilize when the grass is growing The rule behind every date is the same. The University of Florida IFAS says the biggest consideration is to fertilize only when your lawn is actively growing, because outside that window the grass absorbs less and nutrients can wash into nearby water. Texas A&M AgriLife says the same: nutrients are used best when lawns are growing and not under heat or drought stress. That is why one date for the whole country does not work. The grass type tells you when it grows, and your climate tells you when that starts and stops. ## Cool-season lawns: late summer first Penn State Extension says the best times to fertilize cool-season grasses are late summer, late fall and mid- to late spring, and sometimes also early spring. It calls late summer, early to mid-September, the most important feeding, because it helps the turf recover from midsummer heat and drought and supports root growth and winter hardiness. Late fall means the time when leaf growth slows or stops but the soil is not frozen; in most of Pennsylvania that is mid-November. A late-fall feeding can replace the early spring one and gives early green-up. If you skip it, Penn State suggests a light 0.5 to 0.75 pound of nitrogen per 1,000 square feet in early spring, with a heavier late-spring feeding of 0.75 to 1 pound in late May or early June. Penn State’s sample program for a Kentucky bluegrass and ryegrass lawn in Pennsylvania has four dates: mid-March to mid-April, mid-May to early June, September 1 to 20, and November 1 to 15. Its tall fescue example has three: April 15 to June 1, September 1 to 20, and November 1 to 15. These are examples for Pennsylvania lawns kept by a professional, so shift them for your climate. ## Warm-season lawns: after green-up Warm-season grasses grow in the heat, so their window is the opposite. Texas A&M says not to fertilize bermudagrass before full green-up in spring, and not during hot, dry periods in late summer or in late fall and winter when the lawn is dormant or going dormant. UF/IFAS adds that in South Florida turfgrass grows year-round, while in North and Central Florida it grows from about April through September, so the feeding dates follow that growth. The sources do not give a single soil temperature, so use green-up and active growth as your cue. ## How many feedings a year It depends on the grass and the level of care. Texas A&M says a typical plan for a bermudagrass home lawn in Texas ranges from 1 to 4 applications a year, each 0.5 to 1 pound of nitrogen per 1,000 square feet, and notes that older lawns with established roots may need less because they recycle nutrients from clippings. UF/IFAS says a higher-maintenance plan means more feedings in the growing season, a basic plan fewer, and that Florida lawns should never get more than 1 pound of nitrogen per 1,000 square feet at once, whatever the grass. Penn State’s cool-season examples run from two to four feedings, depending on the grass. ## Weather, new lawns and how much Do not fertilize if heavy rain is expected within 24 hours, say both UF/IFAS and Texas A&M, because storms wash the product away before the grass can use it. After applying, water lightly. UF/IFAS says to wet the top half inch of soil, and Texas A&M says less than a quarter inch can move granules in. On a newly planted lawn, UF/IFAS says to wait at least 30 to 60 days after planting. Avoid midsummer feeding on cool-season grass, since Penn State warns that fertilizer applied in heat and drought can stress plants. To get the amount right, work from the nitrogen figure on the bag. Iowa State Extension explains how to turn a rate such as 0.5 pound of nitrogen per 1,000 square feet into pounds of product, using the first number of the fertilizer grade and the area of your lawn. ## Start with a soil test UF/IFAS recommends testing before fertilizing, so you apply only what your soil lacks, and says to use a product made for turf, mostly slow-release nitrogen. Penn State likewise says phosphorus and potassium should follow soil test results. Your state extension service has the local calendar, and your county office can help read it. Where you live also affects local fertilizer rules; Florida has ordinances that vary by city and county, so check yours. Disclosure: Lawnzo is made by Lucernel, the publisher of this article. ## Frequently asked questions ### What is the best month to fertilize a lawn? For cool-season grass in Pennsylvania, Penn State names early to mid-September as the most important time. For warm-season grass, it is the growing season after full green-up. ### Can I fertilize in summer? Not in midsummer heat and drought for cool-season grass, and not in hot, dry late summer for bermudagrass, per Penn State and Texas A&M. Warm-season lawns can be fed during active growth. ### How much nitrogen at a time? Typical single feedings run 0.5 to 1 pound of nitrogen per 1,000 square feet. UF/IFAS says never more than 1 pound at once for Florida lawns. ### Should I fertilize before rain? A light rain or watering after applying helps move it into the soil. Avoid it if heavy rain is expected within 24 hours. ### Is Lawnzo available? See the official app page for current availability and pricing. ## Our pick: Lawnzo, what to do for your lawn, and when Lawnzo builds a seasonal plan from your grass, sun and irrigation, checks each task such as feeding against the forecast, and explains when it keeps, delays or skips a job. It keeps the product limits from the label and a journal of what you applied. It does not replace a soil test or your state extension calendar. - Seasonal plans for your grass type - Keep, delay or skip, with the reason - Work journal with products, quantities and photos [See how Lawnzo works](https://lucernel.com/apps/lawnzo) ## Sources (checked 2026-10-01) - [Penn State Extension: Turfgrass fertilization, a basic guide](https://extension.psu.edu/turfgrass-fertilization-a-basic-guide-for-professional-turfgrass-managers) - [Texas A&M AgriLife Extension: Bermudagrass home lawn management calendar](https://agrilifeextension.tamu.edu/library/landscaping/bermudagrass-home-lawn-management-calendar/) - [UF/IFAS Gardening Solutions: Fertilizing your Florida lawn](https://gardeningsolutions.ifas.ufl.edu/home/care/fertilizer/fertilizing-the-lawn/) - [Iowa State Extension: How to calculate fertilizer rates for the lawn](https://yardandgarden.extension.iastate.edu/how-to/how-calculate-fertilizer-rates-lawn)