USDA zone 7b in Maryland
USDA plant hardiness zone 7b covers 25 locations across Maryland (average annual extreme minimum 5 to 10 °F): Baltimore, MD, Baltimore, MD, Bel Air North, MD, Bel Air South, MD, Bensville, MD, California, MD, and 19 more. Average last spring frost across this group ranges March 24 (Baltimore) to April 26 (Jefferson), and growing seasons run 175–244 days (Jefferson to Baltimore) — even within one state, because hardiness sets winter survival, not planting dates. The table below gives every Maryland location's own frost dates; the printable planting calendar uses Tyaskin, this group's median-season location.
- USDA zone
- 7b5 to 10 °F
- Last frost range
- Mar 24–Apr 26avg, 32°F
- First frost range
- Oct 18–Nov 21avg, 32°F
- Growing season range
- 175–244days
Locations in this group
Every location below shares this zone and a nearby weather station, but keeps its own frost dates — find your town for its own numbers, or use the ZIP planner on the home page for an instant personalized answer.
| Location | Also covers | Nearest station | Last frost | First frost | Season (days) |
|---|---|---|---|---|---|
| Baltimore | Columbia, Ellicott, Severn, Glen Burnie, Odenton, Catonsville, +12 more | Baltimore Wash Intl Ap | Apr 10 | Oct 31 | 204 |
| Baltimore | Towson, Pikesville, Kingsville, Carney, Milford Mill, Perry Hall, +4 more | Md Sci Ctr Baltimore | Mar 24 | Nov 21 | 244 |
| Bel Air North | Perryville | Conowingo Dam | Apr 3 | Nov 6 | 217 |
| Bel Air South | Edgewood, Bel Air North, Fallston, Aberdeen Proving Ground, Kingsville, Aberdeen, +10 more | Aberdeen Phillips Fld | Apr 10 | Oct 30 | 201 |
| Bensville | Dale, Lake Ridge, Woodbridge, Cherry Hill, Montclair, Lorton, +7 more | Quantico Mcas | Mar 28 | Nov 8 | 226 |
| California | Leonardtown, Wildewood | Patuxent River Nas | Mar 29 | Nov 15 | 230 |
| Charlestown | — | Octoraro Lake | Apr 26 | Oct 22 | 179 |
| Chestertown | Centreville, Crumpton, Church Hill, Kennedyville | Chestertown | Apr 3 | Nov 5 | 217 |
| Cordova | Hurlock, Queenstown, Ridgely, Preston, East New Market, Secretary, +2 more | Royal Oak 2 Ssw | Apr 1 | Nov 7 | 220 |
| Croom | Bowie, Dunkirk, Woodmore, Marlboro Meadows, Kettering, Riva, +2 more | Upper Marlboro 3 Nnw | Apr 9 | Oct 29 | 203 |
| Denton | Bridgeville, Harrington, Federalsburg, Greenwood, Houston | Greenwood 2ne | Apr 11 | Oct 30 | 200 |
| Eden | Fruitland, Quantico, Delmar, Princess Anne, Pittsville, Parsonsburg, +4 more | Salisbury Wicomico Rgnl Ap | Apr 10 | Oct 30 | 201 |
| Ellicott | Highland, Brookeville | Laurel 3 W | Apr 5 | Nov 9 | 218 |
| Fairmount | Pocomoke | Wallops Island Flight Fac | Mar 31 | Nov 11 | 225 |
| Fallston | Cockeysville, Randallstown, Sykesville | Cylburn | Apr 2 | Nov 7 | 220 |
| Frederick | Braddock Heights | Frederick Police Brks | Apr 2 | Nov 6 | 218 |
| Germantown | Darnestown, Damascus, Ballenger Creek, Gaithersburg, Poolesville, Montgomery, +7 more | Damascus 3 Ssw | Apr 14 | Oct 29 | 196 |
| Jefferson | — | Sharpsburg 5 S | Apr 26 | Oct 18 | 175 |
| Newark | Snow Hill, Girdletree | Snow Hill 4 N | Apr 10 | Oct 31 | 202 |
| Olney | Ashton-Sandy Spring, Cloverly, Aspen Hill, South Laurel, Silver Spring, Burtonsville, +14 more | Beltsville | Apr 10 | Nov 1 | 202 |
| Olney | Rockville, Gaithersburg, Aspen Hill, North Bethesda, Redland, North Potomac | Rockville 1 Ne | Apr 1 | Nov 6 | 219 |
| Parole | Riva | Annapolis Police Brks | Mar 27 | Nov 13 | 234 |
| Reisterstown | — | Millers 4 Ne | Apr 19 | Oct 25 | 188 |
| Tyaskin * | Sharptown, Mardela Springs, East New Market, Brookview | Vienna | Apr 8 | Nov 4 | 209 |
| Waldorf | Aquasco, Bensville, Cedarville, Hughesville, Huntingtown, Mechanicsville, +11 more | Mechanicsville 5 Ne | Apr 17 | Oct 27 | 195 |
* Tyaskin is this group's median-season location — the calendar below is computed from its data.
Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.
Planting calendar (Tyaskin, representative)
Computed from Tyaskin's average frost dates — the median-season location in this Marylandzone 7b group. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees — your own location's dates may run a week or two earlier or later (see the table above).
- Start indoors
- Plant out
- Fall sowing
- First harvest
| Crop | Frost tolerance | Start indoors | Plant out | First harvest | Fall planting | Season fit |
|---|---|---|---|---|---|---|
| Tomato | Tender | Feb 11 – Feb 25 | Apr 15 – Apr 22 | Jun 14 – Jul 4 | — | matures comfortably |
| Pepper | Very tender | Jan 28 – Feb 11 | Apr 22 – Apr 29 | Jun 21 – Jul 21 | — | matures comfortably |
| Cucumber | Tender | Mar 11 – Mar 18 | Apr 15 – Apr 22 | Jun 4 – Jun 24 | — | matures comfortably |
| Summer squash / zucchini | Tender | — | Apr 15 – Apr 22 | May 30 – Jun 14 | — | matures comfortably |
| Bush bean | Tender | — | Apr 15 – Apr 22 | Jun 4 – Jun 14 | Sep 5 – Sep 15 | matures comfortably |
| Sweet corn | Tender | — | Apr 8 – Apr 22 | Jun 7 – Jul 7 | — | matures comfortably |
| Basil | Very tender | Feb 25 – Mar 11 | Apr 15 – Apr 22 | May 15 – May 30 | — | matures comfortably |
| Lettuce | Half-hardy | Feb 25 – Mar 11 | Mar 11 – Mar 25 | Apr 25 – May 10 | Aug 22 – Sep 6 | matures comfortably |
| Pea | Hardy | — | Feb 25 – Mar 11 | Apr 21 – May 6 | Aug 12 – Aug 27 | matures comfortably |
| Spinach | Hardy | — | Feb 25 – Mar 11 | Apr 6 – Apr 16 | Sep 1 – Sep 11 | matures comfortably |
| Carrot | Half-hardy | — | Mar 18 – Mar 25 | May 17 – Jun 6 | Aug 2 – Aug 22 | matures comfortably |
| Broccoli | Half-hardy | Feb 11 – Feb 25 | Mar 11 – Mar 25 | May 5 – May 25 | Aug 7 – Aug 27 | matures comfortably |
Which crops fit this growing season
Using Tyaskin's own 209-day growing season (32°F, NOAA 1991–2020 median) against each crop's real days-to-maturity range: 12 of 12 crops mature here with comfortable margin. A different location in the table above with a longer or shorter season will get a different mix — the ZIP planner on the home page gives your own.
Frost & freeze dates (Tyaskin)
From NOAA's 1991–2020 Climate Normals at station USC00189140. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 — the conservative date to plant after or harvest before.
| Threshold | Last spring — avg | Last spring — 90%-safe | First fall — avg | First fall — 90%-safe | Season (days) |
|---|---|---|---|---|---|
| 36°F | Apr 21 | May 8 | Oct 23 | Nov 5 | 183 |
| 32°F (freeze) | Apr 8 | Apr 23 | Nov 4 | Nov 20 | 209 |
| 28°F | Mar 27 | Apr 12 | Nov 17 | Dec 5 | 236 |
| 24°F | Mar 13 | Apr 1 | Dec 1 | Dec 22 | 263 |
Growing degree days
Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. This group's median GDD (base 50°F) across all 25 locations is 3,981; Tyaskin's own reading is shown below.
| Model | °F·days | Used for |
|---|---|---|
| Base 50°F (warm-season) | 4,375 | standard warm-season base (tomato, corn, beans) |
| Base 40°F (cool-season) | 7,104 | cool-season crops (brassicas, greens) |
Hardiness zone 7b in Maryland
Zone 7b means an average annual extreme minimum winter temperature of about 5 to 10 °F on the USDA's 2023 map — the number that tells you which perennials, shrubs, and trees reliably survive an average winter here. It does not set your planting dates, which come from the frost calendar above. Maryland spans 5 hardiness zones in this dataset — see all Maryland locations for the full range, including zones6a, 6b, 7a, 8a.
Explore zone 7b in other states at zone 7b, or see all USDA hardiness zones.
Frequently asked questions
- What does USDA hardiness zone 7b mean in Maryland?
- Zone 7b means an average annual extreme minimum winter temperature of 5 to 10 °F — the standard USDA measure of which perennials survive winter. 25 locations in Maryland fall in this zone. It does not set planting dates; see the frost calendar below for that.
- Where in Maryland's zone 7b is the growing season longest?
- Baltimore runs the longest season on this page at about 244 days; Jefferson is shortest at about 175 days — they share the same hardiness zone, but they sit at different weather stations, so their frost calendars differ.
- When should I plant tomatoes in Maryland's zone 7b?
- Using Tyaskin's frost dates (this page's median-season location): start seeds indoors about Feb 11 – Feb 25, then transplant outside about Apr 15 – Apr 22. Your own location in the table above may differ by a week or two — use the ZIP planner on the home page for your exact station's dates.
- Does every location in Maryland's zone 7b have the same frost dates?
- No — they do not all share a weather station, so frost dates vary by a week or more across the 25 locations listed (see the table above for each location's own dates).
Sources & method
Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020, one reading per location's own nearest station (see the table above). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to each location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.