About this guide

What problem this site solves

Homeowners who maintain their own lawns search task-level questions like “when to fertilize Bermuda grass in Atlanta” or “aerating Kentucky bluegrass zone 5.” The honest answer depends on both grass species and USDA hardiness zone, and university extension offices publish the data, but mostly as state-level PDFs that don't cross-reference well. We rebuilt the same information as one page per grass × zone × task with a source citation on every entry.

Methodology

We started with 10 common US residential lawn grasses (4 cool-season, 6 warm-season) and 9 integer USDA hardiness zones (3 through 11). That yields 90 possible grass-zone combinations. After applying published grass-zone tolerance charts, 48 combinations are agronomically reasonable to maintain: we don't generate pages for combinations that don't make sense (Bermuda in zone 3, St. Augustine in zone 5, etc.).

For each valid grass-zone pair, we generated 8 task entries (fertilize, overseed, dethatch, aerate, water, mow, weed-control, fall-cleanup). Each entry carries month-resolution windows derived from one of these university extension sources:

• Penn State Extension: Lawn Management through the Seasons
• UGA (University of Georgia) Extension: Lawns in Georgia
• NC State Extension: Carolina Lawns
• Texas A&M AgriLife Extension: Bermuda, Zoysia, St. Augustine Home Lawn Management Calendars
• UMN (Minnesota) Extension: Lawn Care Calendar
• UC IPM (California): Pest Notes & Turfgrass
• UF/IFAS (Florida) Extension: Florida Lawn Handbook
• Oklahoma State Extension: Lawn Management in Oklahoma

How the entries were written: an AI model (Claude) drafted them from those publications as per-task rules (for example, cool-season grass is fed in early fall and late spring, and the window shifts later as the zone gets warmer), then generated one entry per grass, zone and task. A citation names the publication a rule comes from. It doesn't mean that publication prints the exact month for every grass and zone, so treat the windows as a starting point and check your county extension office before you spend money. Citation links were last checked on October 25, 2026.

Full citation list at /about/sources.

What we don't claim

• Subzone resolution. We collapse subzones (zone 7a and 7b are both shown as “zone 7”). The difference is 1–2 weeks at spring shoulder. If your zone is on the border, treat the window edges with skepticism: verify against a local extension office or your soil-temperature probe.
• Per-state precision. Extension calendars are published at state-level, not zone-level. We map state recommendations to the state's modal USDA zone and adjust by grass-physiology rules for neighboring zones. When we don't have a direct citation for the exact grass-zone combination, the page renders a caveat band.
• Soil-test, pest-ID, or disease-diagnosis advice. Your county extension office does that. We can't.
• Product picks. We don't sell or recommend products. The schedule is the whole site.

How to identify your grass

If you don't know your grass species, look for the seed bag or sod tag your previous owner left in the garage, snap a close-up photo and run it through a grass-ID search, or take a sample to your county extension office (they will identify it free or nearly so). The most useful single tell: warm-season grasses go straw-brown dormant from late autumn through early spring; cool-season grasses stay some shade of green most of the winter (browning only under severe drought).

When was this last reviewed?

Each page's “Source” section names the citation in force at build time. Citation links were last checked on October 25, 2026. Extension sites republish their calendars from time to time, so check the linked page for the current version.