Frost dates for 21233 — Baltimore, MD
Last spring frostMar 24median date
First fall frostNov 21median date
Growing season242 daysfrost-free
Hardiness zone8aZone 8a
How Baltimore compares
- In 8 years out of 10, the last spring frost in Baltimore falls between March 8 and April 4, a 27-day window. The first fall frost falls between November 7 and December 8.
- The median last frost is 12 days earlier than the Maryland median of Apr 5.
- Its 242-day growing season is longer than 93% of the 431 Maryland places with a regular frost season (state median 216 days).
- The last frost is 5 days earlier than the zone 8a median of Mar 29. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 8a chart.
- The weather station records an average of 52 nights a year at or below 32°F.
- Compared with Washington, DC, 55 km away, the last frost here is 5 days earlier than there and the growing season is 18 days longer.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | March 8 |
| 50% (median) | March 24 |
| 10% (safe for tender plants) | April 4 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | November 7 |
| 50% (median) | November 21 |
| 90% (late) | December 8 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Baltimore, MD
Frost dates for 21233 — Baltimore, MD — last frost Mar 24, first frost Nov 21, zone 8a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Dec 30 to Jan 13Start indoors: Dec 30 to Jan 13Transplant outside: Feb 24 to Mar 10
Start indoors: Jan 13 to Jan 27Transplant outside: Apr 7 to Apr 21
Start indoors: Jan 13 to Jan 27Transplant outside: Apr 7 to Apr 21
Start indoors: Jan 27 to Feb 10Transplant outside: Mar 31 to Apr 14
Start indoors: Jan 27 to Feb 10Transplant outside: Mar 3 to Mar 17Sow outdoors: Feb 24 to Mar 31Plant for fall: Sep 26 to Oct 24
Start indoors: Jan 27 to Feb 10Transplant outside: Feb 24 to Mar 10Sow outdoors: Feb 24 to Mar 10Plant for fall: Sep 12 to Oct 3
Start indoors: Jan 27 to Feb 10Transplant outside: Mar 10 to Mar 24Plant for fall: Aug 15 to Sep 5
Start indoors: Jan 27 to Feb 10Transplant outside: Mar 3 to Mar 17Plant for fall: Aug 15 to Sep 5
Start indoors: Jan 27 to Feb 10Transplant outside: Mar 10 to Mar 24Plant for fall: Aug 15 to Sep 5
Start indoors: Feb 10 to Feb 24Transplant outside: Apr 14 to Apr 28Sow outdoors: Apr 14 to Apr 28
Start indoors: Feb 10 to Feb 24Transplant outside: Mar 31 to Apr 14
Sow outdoors: Feb 10 to Mar 3Plant for fall: Aug 29 to Sep 19
Sow outdoors: Feb 10 to Mar 3Plant for fall: Sep 26 to Oct 17
Sow outdoors: Feb 17 to Mar 31Plant for fall: Oct 10 to Oct 31
Start indoors: Feb 24 to Mar 3Transplant outside: Apr 7 to Apr 14Sow outdoors: Mar 31 to Apr 14Plant for fall: Sep 5 to Sep 19
Start indoors: Feb 24 to Mar 3Sow outdoors: Mar 31 to Apr 14Plant for fall: Sep 12 to Sep 26
Start indoors: Feb 24 to Mar 3Sow outdoors: Mar 31 to Apr 14
Start indoors: Feb 24 to Mar 3Transplant outside: Apr 7 to Apr 21
Sow outdoors: Mar 3 to Mar 31Plant for fall: Aug 29 to Sep 12
Sow outdoors: Mar 3 to Mar 31Plant for fall: Sep 12 to Sep 26
Sow outdoors: Mar 3 to Mar 24
Sow outdoors: Mar 10 to Apr 7Plant for fall: Sep 12 to Sep 26
Sow outdoors: Mar 10 to Mar 31Plant for fall: Sep 26 to Oct 17
Sow outdoors: Mar 31 to Apr 21Plant for fall: Sep 5 to Sep 19
Sow outdoors: Mar 31 to Apr 14
Transplant outside: Apr 7 to Apr 28
Plant for fall: Nov 7 to Dec 12
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Baltimore, MD
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Dec 30 – Jan 13 | Feb 24 – Mar 10 | — | — |
| Peppers | Jan 13 – Jan 27 | Apr 7 – Apr 21 | — | — |
| Eggplant | Jan 13 – Jan 27 | Apr 7 – Apr 21 | — | — |
| Tomatoes | Jan 27 – Feb 10 | Mar 31 – Apr 14 | — | — |
| Lettuce | Jan 27 – Feb 10 | Mar 3 – Mar 17 | Feb 24 – Mar 31 | Sep 26 – Oct 24 |
| Kale | Jan 27 – Feb 10 | Feb 24 – Mar 10 | Feb 24 – Mar 10 | Sep 12 – Oct 3 |
| Broccoli | Jan 27 – Feb 10 | Mar 10 – Mar 24 | — | Aug 15 – Sep 5 |
| Cabbage | Jan 27 – Feb 10 | Mar 3 – Mar 17 | — | Aug 15 – Sep 5 |
| Cauliflower | Jan 27 – Feb 10 | Mar 10 – Mar 24 | — | Aug 15 – Sep 5 |
| Okra | Feb 10 – Feb 24 | Apr 14 – Apr 28 | Apr 14 – Apr 28 | — |
| Basil | Feb 10 – Feb 24 | Mar 31 – Apr 14 | — | — |
| Peas | — | — | Feb 10 – Mar 3 | Aug 29 – Sep 19 |
| Spinach | — | — | Feb 10 – Mar 3 | Sep 26 – Oct 17 |
| Radishes | — | — | Feb 17 – Mar 31 | Oct 10 – Oct 31 |
| Cucumbers | Feb 24 – Mar 3 | Apr 7 – Apr 14 | Mar 31 – Apr 14 | Sep 5 – Sep 19 |
| Zucchini & Summer Squash | Feb 24 – Mar 3 | — | Mar 31 – Apr 14 | Sep 12 – Sep 26 |
| Winter Squash & Pumpkins | Feb 24 – Mar 3 | — | Mar 31 – Apr 14 | — |
| Melons & Watermelon | Feb 24 – Mar 3 | Apr 7 – Apr 21 | — | — |
| Carrots | — | — | Mar 3 – Mar 31 | Aug 29 – Sep 12 |
| Beets | — | — | Mar 3 – Mar 31 | Sep 12 – Sep 26 |
| Potatoes | — | — | Mar 3 – Mar 24 | — |
| Swiss Chard | — | — | Mar 10 – Apr 7 | Sep 12 – Sep 26 |
| Cilantro | — | — | Mar 10 – Mar 31 | Sep 26 – Oct 17 |
| Green Beans | — | — | Mar 31 – Apr 21 | Sep 5 – Sep 19 |
| Sweet Corn | — | — | Mar 31 – Apr 14 | — |
| Sweet Potatoes | — | Apr 7 – Apr 28 | — | — |
| Garlic | — | — | — | Nov 7 – Dec 12 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Md Sci Ctr Baltimore, MD weather station, about 1 km away (elevation 20 ft (6 m)).
ZIP codes in Baltimore: 21201 21202 21203 21205 21206 21209 21210 21211 21212 21213 21214 21215 21216 21217 21218 21223 21224 21229 21230 21231 21233 21235 21239 21240 21241 21250 21251 21263 21264 21270 21273 21275 21278 21279 21280 21281 21287 21288 21289 21290 21297 21298
Frost dates near Baltimore
- Brooklyn Mar 24 · Nov 21
- Halethorpe Apr 10 · Oct 31
- Linthicum Heights Apr 10 · Oct 31
- Curtis Bay Mar 24 · Nov 21
- Catonsville Apr 2 · Nov 7
- Gwynn Oak Apr 2 · Nov 7
- Dundalk Mar 24 · Nov 21
- Rosedale Mar 24 · Nov 21
Frequently asked questions
When is the last frost in Baltimore, MD?
The median last spring frost in Baltimore, MD is March 24. There is still about a 10% chance of frost after April 4, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Baltimore, MD?
The median first fall frost is November 21, with about a 10% chance of frost before November 7.
How long is the growing season in Baltimore, MD?
About 242 days between the median last spring frost and first fall frost.
What planting zone is Baltimore, MD?
Baltimore, MD is in USDA hardiness zone 8a.