Can I Grow Shiso in Virginia?

USDA Zones 5b-8b · Plant zone range Data pending

Yes — Strong Match

shiso is grown as an annual, so season length decides it here, not a winter zone — and Virginia's typical season runs ~224 frost-free days against the ~80 shiso needs.

Sow by about Aug 29

Shiso is grown as an annual, so what decides it here is season length, not a winter zone. It needs about 80 frost-free days and a typical Virginia season runs ~224 frost-free days, leaving 144 days of slack. That is room to sow as late as about Aug 29 and still finish before the usual first freeze (Nov 7).

Want more weeks at either end of that window? How to buy the weeks →

80 frost-free days required against Virginia’s ~224-day season. NOAA Regional Climate Centers ACIS 1991-2020 (28°F killing freeze), state median across counties, via stateClimateData.ts.

Score your parcel · free

Your yard isn't the whole zone.

Shiso is grown as an annual, so your winter zone isn't the deciding factor — your frost-free window is. A typical Virginia site runs ~224 frost-free days, but that is a state median, not your yard: slope, trees, and low spots move the last-frost date across a single parcel. Enter your address and we'll score shiso against your land's actual frost dates, sun, and soil.

We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.

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Zone Comparison

Shiso Needs

  • USDA Zones: Data pending
  • Frost-Free Days: 80+
  • Sun: Full Sun
  • Mature size: 2 ft tall
  • Picking window: ~60 days of harvest
  • Drought tolerance: High

Virginia Has

  • USDA Zones: 5b-8b
  • Last Hard Freeze (28°F): Mar 22 - Apr 2
  • First Hard Freeze (28°F): Nov 2 - Nov 17
  • Annual Rainfall: 36-50 inches
  • Common Soils: Red clay (Piedmont), Silt loam, Sandy loam (Tidewater)

Preferred Soil pH

3.5 (Acidic)7.0 (Neutral)9.0 (Alkaline)
Highlighted range: pH 5.57.5

Plant data: USDA PLANTS Database / Growable Ground plant catalog. State data: USDA ARS PHZM 2023, NOAA Climate Normals, NRCS SSURGO.

When to Plant Shiso in Virginia

The frost window

Across Virginia, the last spring hard freeze (28°F) clears between Mar 22 and Apr 2, and the first fall hard freeze lands between Nov 2 and Nov 17 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 214-day window you can count on — up to 240 days on a mild site in a kind year. That marks the hard freeze, not the last light frost, so tender transplants usually wait another 2-3 weeks.

When to start the seed

Those dates are when shiso goes out, not when it starts. It is sown under cover about 4 weeks ahead, so counting back from Virginia's late-side last freeze of Apr 2 is what fixes your sowing date — and a yard that clears frost earlier than the state's late date starts earlier still.

Days to maturity vs. the window

At 70 days to maturity (USDA PLANTS Database), counting from the last hard freeze it ripens with 144 days to spare even in Virginia's tightest freeze scenario — room for a later start or a second sowing.

Timing tuned to sub-state frost dates — Highland County, not the statewide average.

Frost window: NOAA Climate Normals 1991-2020. Plant timing fields: USDA PLANTS Database. Your site's own frost dates can run earlier or later than the state range — a parcel report pins them down.

Growing Season Fit

Frost-free days

Shiso wants 80+ frost-free days; a typical Virginia site sees ~224 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves comfortable headroom for succession planting.

Growing degree days

Shiso needs ~1400 GDD (base 50°F) to ripen. The state median runs ~3662 GDD (from PRISM 1991-2020 climate normals), so Virginia's typical season clears that easily.

GDD and chill-hour figures are computed from PRISM 1991-2020 monthly climate normals; frost-free days from NOAA Regional Climate Centers ACIS, 1991-2020. Each is the state median across its counties (P25/P75 span the within-state spread). Hardiness-zone range is USDA PHZM 2023.

Soil + Drainage Fit

Shiso likes near-neutral soil (pH 5.5-7.5). That's the common-ground band across Virginia's red clay (piedmont) and silt loam — a soil test confirms it for your site. It will grow across that whole span, but it does best between pH 5.5 and 6 — worth knowing before you decide whether a Virginia soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Virginia site is heavier clay or sits in a low spot, raised beds or amendment with compost solve it.

Your land, not the state average

Virginia's soils run mostly fine sandy loam, but SSURGO maps the series, texture, and drainage under your exact parcel. Shiso needs about 19 inches of workable depth, so it is that horizon — not the surface — you are testing for. That map unit, not the state average, decides how shiso performs.

Check your parcel → Source: USDA NRCS SSURGO.

Plant pH and drainage requirements from USDA PLANTS Database. Virginia soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.

Shiso in Virginia — Quick Answer

  • Verdict: Yes — Strong Match
  • Plant Zones: Data pending (USDA PLANTS Database)
  • State Zones: 5b-8b (USDA ARS PHZM 2023)
  • Growing Season: 28°F hard freezes about Mar 22 - Apr 2 to Nov 2 - Nov 17 (NOAA Regional Climate Centers ACIS, 1991-2020)
  • Days to Maturity: 70 days

What Else to Consider for Shiso in Virginia

Zone compatibility tells you about winter cold survival — but Virginia growers also need to think about:

Heavy Piedmont red clay requires amendment

Humidity and heat in summer promote disease

Deer pressure is heavy in suburban and rural areas

Growing shiso here specifically

Virginia's soils run mostly fine sandy loam (Ultisols), and whether that suits shiso's pH 5.5–7.5 preference comes down to your exact parcel, not the statewide picture.

Pull your parcel's SSURGO map unit, test pH, and amend toward shiso's 5.5–7.5 target before planting. How to handle it →

What to actually do about these — and the constraints that apply to every Virginia grower, not just shiso — is covered on the Virginia growing guide.

Timing shifts within Virginia

Virginia isn't one climate. In Highland County, the last hard freeze (28°F) holds until about Apr 27 — roughly 30 days later than the recorded state median — so plant shiso to your county's window, not the statewide date.

Shiso needs about 80 days of frost-free season to complete its cycle. Even Highland County — Virginia’s shortest season at 176 frost-free days — clears that by 96 days, so season length isn’t the constraint anywhere in Virginia. What varies is your own parcel.

Across Virginia’s 133 counties the frost-free season runs from 176 days in Highland County to 289 days in Hampton County — a spread of 113 days, which is why a single statewide planting date misleads. The median Virginia county sees 224 frost-free days, leaving shiso about 144 days of slack on a typical parcel — room for a second sowing where the season runs long.

County last-freeze dates and frost-free day counts: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F freeze (earlier than the folk 32°F "last frost"). Shiso's 80-day requirement: USDA PLANTS / Growable Ground plant database (minimum frost-free days). A parcel report resolves your address's own frost dates.

Pollinator + Wildlife Value

Shiso draws honeybees (low value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, shiso can only work that bloom inside Virginia's frost window — roughly 224 days, opening after the last 28°F freeze (Mar 22 - Apr 2) and closing at the first (Nov 2 - Nov 17), per NOAA Regional Climate Centers ACIS, 1991-2020.

Good to Know Before You Plant Shiso

Shiso is listed as toxic to dogs, cats (all) at a mild level (Cornell). Most listed plants only cause brief upset — a raised bed or a fenced corner usually keeps curious pets clear. Worth knowing for placement: in Virginia this is a one-season plant and the first hard freeze (Nov 2 - Nov 17) takes it down, so the exposure above is a summer-long one rather than something standing in the bed all year.

Recommended Shiso Varieties for Virginia

Virginia publishes no state variety trial for shiso, so we won't invent a "best for Virginia" list. Choose types rated to your USDA hardiness zone (5b-8b), and confirm winter survival and drainage against your own parcel.

Virginia Cooperative Extension

For Virginia-specific cultivar recommendations, planting calendars, and pest pressure for shiso, the canonical source is Virginia Cooperative Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.

Is Shiso native to Virginia?

No — the USDA PLANTS Database lists Shiso as introduced rather than native in the Lower 48, so it is not part of Virginia's native flora. It grows here as a garden plant; pairing it with a few Virginia natives keeps local pollinators fed too.

Looking for plants that belong here? The Virginia growing guide lists USDA-documented natives for the state.

Native-range data: USDA PLANTS Database state-distribution records, accessed 2026-07-01.

Common Questions About Growing Shiso in Virginia

When can I plant Shiso in Virginia?

Virginia's last spring hard freeze (28°F) clears between Mar 22 and Apr 2, and the first fall hard freeze lands between Nov 2 and Nov 17 (NOAA Regional Climate Centers ACIS, 1991-2020). Time outdoor planting to after the last hard freeze for your specific site — a further two to three weeks for anything tender — and count back from those dates for transplant scheduling.

Can Shiso mature before first frost in Virginia?

Yes — Shiso matures in 70 days (USDA PLANTS Database), and Virginia's dependable hard-freeze-free window runs 214 days (NOAA Regional Climate Centers ACIS, 1991-2020), leaving 144 days of margin. Plant once the last hard freeze has passed — two to three weeks later for anything tender — and it ripens ahead of the first fall freeze.

What hardiness zone is Shiso grown in across Virginia?

Virginia spans USDA hardiness zones 5b-8b (USDA ARS PHZM 2023). Shiso carries a range of zones Data pending, so the overlap zones are where outdoor growing is most reliable.

How many frost-free days does a typical Virginia site have?

A typical Virginia site sees ~224 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Shiso needs 80+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date. In cooler counties like Highland, the freeze-free season runs shorter than the state average, so verify your own county's window.

Is Shiso native to Virginia?

No — the USDA PLANTS Database lists Shiso as introduced rather than native in the Lower 48, so it is not part of Virginia's native flora. It grows here as a garden plant; pairing it with a few Virginia natives keeps local pollinators fed too.

How should I amend the soil for Shiso in Virginia?

Shiso prefers pH 5.5-7.5 and well (dry spells) drainage (Growable Ground Plant Database). That sits in the common-ground band across Virginia soils — a 30-minute soil test from a local Extension lab confirms it for your specific site.

Will Shiso actually grow on my specific land in Virginia?

State-level zone + climate data is a sketch. A Growable Ground parcel report scores shiso against your address's exact soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.

Free Report

Check your specific parcel in Virginia

State-level data is a sketch. Your Growable Ground report scores shiso against your parcel's exact soil, sun, drainage, and frost data — not zone averages.

Three things about your lot that Virginia shiso averages can't show:

Your soil pHYour frost-free days — Virginia averages 224Your sun & shade

We read public map data around Virginia — soil, climate, flood, and parcel records. How we handle your address.

25+ data sources read at your address, not the Virginia shiso average

Analysis by the Growable Ground research team, grounded in USDA PLANTS, USDA NRCS SSURGO, NOAA Climate Normals (1991-2020), and named Cooperative Extension sources. How we know →

Cite this dataset

Kirchick, M. (2026). Growable Ground Plant Database [Data set]. Zenodo. https://doi.org/10.5281/zenodo.21435643

Licensed CC BY-NC 4.0. DOI 10.5281/zenodo.21435643

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