# Lawn care calendar for Maryland: when to fertilize and seed

> Maryland lawn calendar for tall fescue and zoysia: University of Maryland timing, the fertilizer law (March 1 to November 15, nitrogen caps), NOAA frost dates.

Canonical: https://lucernel.com/guides/lawn-care-calendar/maryland
Last updated: 2026-10-21

Maryland writes the fertilizer calendar into law: no lawn fertilizer before March 1 or after November 15, and per-application and yearly nitrogen caps. University of Maryland Extension's seasonal calendar fits inside that window, and for most lawns the important work happens in late summer and fall.

**Fertilize tall fescue from September to November 15, seed by mid-October, and keep fertilizer off the lawn before March 1.** University of Maryland Extension calls late summer into early autumn the prime season for tall fescue: seed or sod by mid-October, aerate, lime and fertilize between mid-August and mid-October. A late application is allowed until the law's November 15 cutoff. Zoysia lawns are on the opposite schedule: dormant from mid-October to mid-May, planted in late May, and last fertilized by mid-August. Under the Fertilizer Use Act homeowners may apply no more than 0.9 pound of nitrogen per 1,000 square feet at a time. (University of Maryland Extension; Agriculture Article 8-803.5)

| Month | Tall fescue and fine fescue | Zoysia |
| --- | --- | --- |
| January | Sharpen mower blades; stay off frozen turf | Dormant |
| February | Do not use fertilizer to melt ice; stay off frozen turf | Dormant |
| March | Fertilizer allowed from March 1; a crabgrass pre-emergent is an option, not a routine | Pull winter weeds by hand while the soil is moist |
| April | Spring feeding window opens for weak or thin lawns; seed spots after mid-April | Weed by hand |
| May | Spring feeding window runs to mid-May or Memorial Day | Dormant to about mid-May; plant in late May in central Maryland |
| June | Skip irrigating an established lawn; no fertilizer | Dethatch if over half an inch, aerate, fertilize once green |
| July | Dormant in heat is normal; do not mow or fertilize | Mow regularly while growing |
| August | From mid-August: weeds, lime and fertilizer by soil test, aeration | Last fertilizer by mid-August |
| September | Prime season: seed, aerate, fertilize at 0.7 to 0.9 lb N | Mow while growing |
| October | Sow seed or sod by mid-October; fertilize through November 15 | Dormant from mid-October |
| November | Fertilize before November 15; last mow in late November, half an inch shorter | Dormant |
| December | No fertilizer after November 15 | Dormant |

The source calendar gives its planting dates for central Maryland.

## Which grasses grow where in Maryland

University of Maryland Extension says that for most Maryland lawns the dominant grass is either tall fescue or zoysia, and that you should base care on whichever dominates a mixed lawn. Cool-season grasses (tall fescue, Kentucky bluegrass, fine fescue) are fed late summer into autumn; warm-season grasses (zoysia, bermudagrass) are fed late spring into summer.

Mowing heights from the extension: tall fescue 3 to 4 inches, Kentucky bluegrass 2.5 to 3.5, fine fescue 3 to 4, zoysia 1.5 to 2.5 and bermudagrass 1 to 1.5. Fine fescue lawns can go unmown for long stretches, and the extension says to cut at 4 to 5 inches once spring seed heads turn brown. Mowing the last time of the season half an inch shorter helps against snow mold.

## Frost dates from NOAA

Dates are the NOAA 1991-2020 normals for the last spring and first fall 32 F freeze at 50% probability. Baltimore-Washington International averages April 10 and October 31. Salisbury-Wicomico Regional Airport on the Eastern Shore averages April 10 and October 30.

Our arithmetic: both stations have about 203 to 204 days between those dates, so a single central Maryland calendar fits both.

## Spring

For tall fescue, skip spring fertilizing if you fed one or two times last autumn. A single spring application is warranted for weak, sparse or heavily used lawns, or ones with a history of crabgrass or red thread, and the window is April to about mid-May, or Memorial Day in a mild spring. Weed-and-feed products count against your yearly nitrogen limit, and the extension advises against them.

UMD says herbicide should be a last resort, including pre-emergents, and a pre-emergent usually blocks seeding in the same season. Check local rules too: Montgomery County restricts lawn pesticides. Seed in spring only if the project cannot wait until late summer, and not until soil warms, about mid-April in central Maryland.

## Summer

Established tall fescue goes dormant in hot, dry weather and turns brown, which is normal. Skip irrigation or water just enough to keep roots alive in a prolonged drought, and do not mow or fertilize dormant grass. Grass in active growth does best with about 1 inch of water a week, which soaks about 6 inches deep; water in the morning to limit disease.

Zoysia is very drought-tolerant and shows stress by turning paler and not springing back after being stepped on. Feed it a second time only if the lawn was planted at least a month earlier or has poor vigor, and no later than mid-August to reduce winter injury.

## Fall

UMD's tall fescue calendar for mid-August to mid-October: control weeds, apply lime and fertilizer by soil test, core aerate compacted areas before overseeding, and sow seed or lay sod no later than mid-October. Seed takes about two weeks to germinate, and killing frosts in November can damage young seedlings. Its nitrogen table for tall fescue is 0.7 to 0.9 pound per 1,000 square feet in September and again from October through November 15, with up to 2.7 pounds a year, and an optional 0.5 to 0.9 pound in May or early June.

From late October to mid-November, mulch fallen leaves with the mower or move them to beds, then fertilize before November 15. The extension warns that using fertilizer to melt ice breaks the state's law.

## Maryland's Fertilizer Use Act

Agriculture Article section 8-803.5 covers anyone applying fertilizer to property that is not used for agriculture. No fertilizer containing nitrogen or phosphorus on turf before March 1 or after November 15, or when the ground is frozen, and none on an impervious surface. Keep 15 feet back from surface water, ponds, lakes, rivers, streams and ditches, or 10 feet with a drop spreader, a rotary spreader with a deflector or a targeted spray.

A person other than a professional applicator may not apply more than the University of Maryland's annual recommended rate, and fertilizer may not exceed 0.7 pound of water-soluble nitrogen or 0.9 pound of total nitrogen per 1,000 square feet per application, at least 20 percent slow-release. Phosphorus on turf is limited to cases such as a soil test taken within three years that shows a need. Lawn fertilizer sold for established lawns must be low in phosphorus under section 6-222. The lawn fertilizer calculator on this site shows how much of a bag stays under 0.9 pound of nitrogen for your lawn size.

## Frequently asked questions

### When can I fertilize my lawn in Maryland?

Between March 1 and November 15, and not on frozen ground. For tall fescue, UMD's best windows are September and October through November 15.

### How much nitrogen can I apply at once in Maryland?

Up to 0.9 pound of total nitrogen per 1,000 square feet per application, no more than 0.7 pound of it water-soluble, using a fertilizer that is at least 20 percent slow-release.

### When should I seed grass in Maryland?

For tall fescue and fine fescue, late summer into early autumn, no later than mid-October. Zoysia is planted in late May to June.

### Can I put fertilizer on my driveway or use it to melt ice?

No. Maryland bars fertilizer on impervious surfaces and UMD notes that using fertilizer to melt ice violates the law.

### Can Lawnzo help me follow a Maryland lawn schedule?

Lawnzo for iPhone turns a calendar like this one into a plan for each lawn you keep, using your grass type, sun and irrigation. Each job is checked against the weather forecast, and the app tells you the reason when it moves one. You can log products and photos in the journal.

## Sources (checked 2026-10-02)

- [University of Maryland Extension, Lawn maintenance calendar](https://extension.umd.edu/resource/lawn-maintenance-calendar)
- [University of Maryland Extension, Maintaining an established lawn](https://extension.umd.edu/resource/maintaining-established-lawn)
- [University of Maryland Extension, Lawn grasses grown in Maryland](https://extension.umd.edu/resource/lawn-grasses-grown-maryland)
- [Maryland Code, Agriculture Article, section 8-803.5](https://mgaleg.maryland.gov/mgawebsite/Laws/StatuteText?article=gag&section=8-803.5&enactments=false)
- [Maryland Code, Agriculture Article, sections 6-222 and 6-224 (lawn fertilizer sale and label limits)](https://mgaleg.maryland.gov/mgawebsite/Laws/StatuteText?article=gag&section=6-224&enactments=false)
- [NOAA NCEI 1991-2020 normals: frost dates for Baltimore-Washington International Airport, Salisbury-Wicomico Regional Airport (API query)](https://www.ncei.noaa.gov/access/services/data/v1?dataset=normals-annualseasonal-1991-2020&stations=USW00093721,USW00093720&dataTypes=ANN-TMIN-PRBLST-T32FP50,ANN-TMIN-PRBFST-T32FP50&format=json)
- [NOAA NCEI, U.S. Climate Normals 1991-2020 (product page)](https://www.ncei.noaa.gov/products/land-based-station/us-climate-normals)
- [NOAA NCEI, station inventory (GHCN-Daily station list)](https://www.ncei.noaa.gov/pub/data/ghcn/daily/ghcnd-stations.txt)