What does USDA hardiness zone 6a mean in Virginia?

Zone 6a means an average annual extreme minimum winter temperature of −10 to −5 °F — the standard USDA measure of which perennials survive winter. 1 location in Virginia fall in this zone. It does not set planting dates; see the frost calendar below for that.

When should I plant tomatoes in Virginia's zone 6a?

Using McDowell's frost dates (this page's median-season location): start seeds indoors about Mar 13 – Mar 27, then transplant outside about May 15 – May 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 Virginia's zone 6a 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 1 locations listed (see the table above for each location's own dates).

USDA zone 6a in Virginia

−10 to −5 °F avg. annual extreme minimum · 1 location in this group · NOAA 1991–2020 normals

USDA plant hardiness zone 6a covers 1 location across Virginia (average annual extreme minimum −10 to −5 °F): McDowell, VA. Average last spring frost across this group ranges May 8 and growing seasons run 148 days — even within one state, because hardiness sets winter survival, not planting dates. The table below gives every Virginia location's own frost dates; the printable planting calendar uses McDowell, this group's median-season location.

USDA zone: 6a−10 to −5 °F
Last frost range: May 8avg, 32°F
First frost range: Oct 5avg, 32°F
Growing season range: 148days

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.

Own frost dates per location.
Location	Also covers	Nearest station	Last frost	First frost	Season (days)
McDowell *	Monterey	Mustoe 1 Sw	May 8	Oct 5	148

* McDowell 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 (McDowell, representative)

Computed from McDowell's average frost dates — the median-season location in this Virginiazone 6a 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).

Crop

JanFebMarAprMayJunJulAugSepOctNovDec

Tomato

Pepper

Cucumber

Summer squash / zucchini

Start indoors
Plant out
Fall sowing
First harvest

Planting windows for McDowell (Virginia, zone 6a), this group's representative location.
Crop	Frost tolerance	Start indoors	Plant out	First harvest	Fall planting	Season fit
Tomato	Tender	Mar 13 – Mar 27	May 15 – May 22	Jul 14 – Aug 3	—	matures comfortably
Pepper	Very tender	Feb 27 – Mar 13	May 22 – May 29	Jul 21 – Aug 20	—	matures comfortably
Cucumber	Tender	Apr 10 – Apr 17	May 15 – May 22	Jul 4 – Jul 24	—	matures comfortably
Summer squash / zucchini	Tender	—	May 15 – May 22	Jun 29 – Jul 14	—	matures comfortably
Bush bean	Tender	—	May 15 – May 22	Jul 4 – Jul 14	Aug 6 – Aug 16	matures comfortably
Sweet corn	Tender	—	May 8 – May 22	Jul 7 – Aug 6	—	matures comfortably
Basil	Very tender	Mar 27 – Apr 10	May 15 – May 22	Jun 14 – Jun 29	—	matures comfortably
Lettuce	Half-hardy	Mar 27 – Apr 10	Apr 10 – Apr 24	May 25 – Jun 9	Jul 23 – Aug 7	matures comfortably
Pea	Hardy	—	Mar 27 – Apr 10	May 21 – Jun 5	Jul 13 – Jul 28	matures comfortably
Spinach	Hardy	—	Mar 27 – Apr 10	May 6 – May 16	Aug 2 – Aug 12	matures comfortably
Carrot	Half-hardy	—	Apr 17 – Apr 24	Jun 16 – Jul 6	Jul 3 – Jul 23	matures comfortably
Broccoli	Half-hardy	Mar 13 – Mar 27	Apr 10 – Apr 24	Jun 4 – Jun 24	Jul 8 – Jul 28	matures comfortably

Which crops fit this growing season

Using McDowell's own 148-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 (McDowell)

From NOAA's 1991–2020 Climate Normals at station USC00445880. 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.

Freeze probabilities by temperature threshold (MM/DD, NOAA 1991–2020), McDowell.
Threshold	Last spring — avg	Last spring — 90%-safe	First fall — avg	First fall — 90%-safe	Season (days)
36°F	May 21	Jun 4	Sep 25	Oct 6	127
32°F (freeze)	May 8	May 26	Oct 5	Oct 19	148
28°F	Apr 29	May 18	Oct 17	Oct 30	171
24°F	Apr 13	May 3	Oct 27	Nov 9	196

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 1 locations is 2,319; McDowell's own reading is shown below.

Annual growing degree days for McDowell (°F·days, NOAA 1991–2020).
Model	°F·days	Used for
Base 50°F (warm-season)	2,319	standard warm-season base (tomato, corn, beans)
Base 40°F (cool-season)	4,486	cool-season crops (brassicas, greens)

Hardiness zone 6a in Virginia

Zone 6a means an average annual extreme minimum winter temperature of about −10 to −5 °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. Virginia spans 6 hardiness zones in this dataset — see all Virginia locations for the full range, including zones6b, 7a, 7b, 8a, 8b.

Explore zone 6a in other states at zone 6a, or see all USDA hardiness zones.

Frequently asked questions

What does USDA hardiness zone 6a mean in Virginia?: Zone 6a means an average annual extreme minimum winter temperature of −10 to −5 °F — the standard USDA measure of which perennials survive winter. 1 location in Virginia fall in this zone. It does not set planting dates; see the frost calendar below for that.
When should I plant tomatoes in Virginia's zone 6a?: Using McDowell's frost dates (this page's median-season location): start seeds indoors about Mar 13 – Mar 27, then transplant outside about May 15 – May 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 Virginia's zone 6a 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 1 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.