Alexandria, Virginia: planting zone & frost dates
Alexandria is in USDA plant hardiness zone 8a, where the average coldest winter night reaches 10 to 15°F (-12.2 to -9.4°C). The typical last spring frost is around Mar 30 and the first fall frost around Nov 12.
Frost dates
| Probability | Last spring frost (32°F) | First fall frost (32°F) |
|---|---|---|
| Safer (10% risk) | Apr 6 | Nov 5 |
| Typical planning date (30% risk) | Mar 30 | Nov 12 |
| Median (50%) | Mar 24 | Nov 18 |
How to read this: after the spring "10% risk" date, a 32°F frost happens in only about 1 year in 10. In fall, the "10% risk" date is the early end — a frost before it happens about 1 year in 10.
Frost data comes from NOAA station WASHINGTON REAGAN AP, VA (USW00013743), 3.4 mi (5.4 km) from the city center and 154 ft lower than the city center (-47 m). Record used for the 1991–2020 normals: 27 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Alexandria
Alexandria spans more than one half-zone. Share of the city's land area by zone (via its 7 ZIP codes): 8a (58%), 7b (42%). The headline zone is the one covering the most land. Look up your ZIP for your exact zone.
Vegetable planting calendar for Alexandria
Dates are counted from the 30%-risk frost dates above (last frost Mar 30, first frost Nov 12). Shift a week later in cold spots or low-lying ground.
| Crop | Start indoors | Transplant / plant out | Direct sow | Fall crop sow/plant |
|---|---|---|---|---|
| Tomato | Feb 2 – Feb 16 | Apr 6 – Apr 20 | — | — |
| Pepper | Jan 19 – Feb 2 | Apr 13 – Apr 27 | — | — |
| Lettuce | Feb 16 – Mar 2 | Mar 16 – Apr 6 | Mar 2 – Apr 13 | Sep 3 – Oct 1 |
| Green Beans | — | — | Apr 6 – May 11 | Aug 20 – Sep 3 |
| Sweet Corn | — | — | Apr 6 – May 4 | — |
| Zucchini & Summer Squash | Mar 2 – Mar 9 | Apr 6 – Apr 20 | Apr 6 – Apr 27 | Aug 20 – Sep 3 |
| Cucumber | Mar 2 – Mar 9 | Apr 13 – Apr 20 | Apr 6 – Apr 27 | Aug 20 – Sep 3 |
| Carrot | — | — | Mar 9 – Apr 13 | Aug 20 – Sep 3 |
| Onion | Jan 5 – Jan 19 | Mar 2 – Mar 16 | — | — |
| Potato | — | Mar 2 – Mar 23 | — | — |
| Basil | Feb 16 – Mar 2 | Apr 13 – Apr 27 | Apr 13 – May 4 | — |
| Spinach | — | — | Feb 16 – Mar 16 | Sep 17 – Oct 15 |
| Kale | Feb 2 – Feb 16 | Mar 2 – Mar 23 | Mar 2 – Mar 23 | Sep 3 – Oct 1 |
| Broccoli | Feb 2 – Feb 16 | Mar 16 – Apr 6 | — | Aug 20 – Sep 3 |
| Peas | — | — | Feb 16 – Mar 9 | Sep 3 – Sep 17 |
| Eggplant | Jan 19 – Feb 2 | Apr 13 – Apr 27 | — | — |
| Cabbage | Feb 2 – Feb 16 | Mar 2 – Mar 16 | — | Aug 20 – Sep 3 |
| Radish | — | — | Feb 23 – Apr 13 | Oct 1 – Oct 29 |
| Strawberry | — | Mar 2 – Mar 23 | — | — |
| Beets | — | — | Mar 9 – Apr 20 | Sep 3 – Sep 17 |
Nearby cities in Virginia
- Richmond — zone 7b, last frost Apr 9, first frost Oct 31
- Newport News — zone 8a, last frost Apr 7, first frost Nov 4
- Hampton — zone 8b, last frost Mar 30, first frost Nov 10
- Norfolk — zone 8b, last frost Mar 23, first frost Nov 18
- Portsmouth — zone 8b, last frost Mar 30, first frost Nov 11
- Suffolk — zone 8a, last frost Apr 1, first frost Nov 9
More: all Virginia cities · other zone 8a cities: Charlotte, NC, Memphis, TN, Atlanta, GA, Raleigh, NC, Greensboro, NC, Durham, NC, Winston-Salem, NC, Chesapeake, VA
Alexandria gardening questions
When is the last frost in Alexandria, VA?
Plan around Mar 30. At NOAA's Washington Reagan Airport, VA station, 3.4 mi from the city center, there is a 30% chance of a 32°F frost after that date. Half of springs have their last frost by Mar 24, and after Apr 6 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Mar 12. The 90% and 10% dates are 30 days apart, close to the 36-day median for cities on this site.
When should I plant tomatoes in Alexandria, VA?
Start seeds indoors Feb 2 – Feb 16 and set transplants outside Apr 6 – Apr 20, once nights stay above 50°F and the soil is near 60°F. That leaves 227 days between the 30% frost dates, enough for most varieties including 80–85-day slicers. More: tomato planting dates by zone.
How long is the growing season in Alexandria?
About 241 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 220 days, and in 1 year in 10 it runs 265 days or more. In fall there is a 10% chance of frost by Nov 5 and a 30% chance by Nov 12. That ranks 2nd longest of 11 Virginia cities on this site.
When should I plant a fall garden in Alexandria?
Count back from the first fall frost (Nov 12): transplant broccoli Aug 20 – Sep 3; sow kale Sep 3 – Oct 1; sow lettuce Sep 3 – Oct 1; sow radishes Oct 1 – Oct 29. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Dec 3. How the math works: succession and fall planting.
Did Alexandria's hardiness zone change on the 2023 map?
Yes. Most of Alexandria was zone 7b on the 2012 map and is zone 8a on the 2023 map — half a zone warmer, like about 56% of U.S. ZIP codes. The shift comes from a newer 1991–2020 averaging period plus more weather stations and better mapping; it does not mean last frost comes earlier. Why the 2023 map is warmer.
Is all of Alexandria in zone 8a?
No. Zone 8a covers about 58% of the city's land; the rest is in 7b (42%), measured across the city's 7 ZIP codes. Check your own ZIP code in the table above or with the ZIP lookup.