Vietnamese coriander (Persicaria odorata), photographi

Can I Grow Vietnamese Coriander in Indiana?

USDA Zones 5b-7b · Plant zone range 9-11

Unlikely — Zone Mismatch

Vietnamese coriander (zones 9-11) does not overlap with Indiana's zone range (5b-7b). Growing outdoors is unlikely without significant protection.

2 zones short — what would close it

Vietnamese Coriander is hardy to zone 9, and the warmest ground in Indiana is zone 7 — 2 zones short. Planted in open ground it will not survive a Indiana winter. To grow it here, grow vietnamese coriander in an earth-sheltered greenhouse — its modeled 2.5-zone lift covers this gap.

An earth-sheltered greenhouse is the lift this needs. How a greenhouse changes what you can grow →

Zone math from 9-11 (plant) against 5-7 (Indiana). Lift modeled by crop_engine.GREENHOUSE_ZONE_MODIFIER_BY_SUBTYPE['earth_sheltered'] (+2.5 zones) via api/fast_sections.py Unlock Engine v2.

Vietnamese Coriander in Indiana — the short answer

Vietnamese Coriander in Indiana: hardy in zones 9–11, part sun, against a state median of ~209 frost-free days.

Plant zones
9-11
Manual horticultural correction (source not retained); NC State Extension and Missouri Botanical Garden, with the remaining rows from other published sources or Growable Ground compilation
Indiana zones
5b-7b
USDA PHZM 2023
Frost window
Apr 4 - Apr 9 – Oct 30 - Nov 4
NOAA RCC ACIS 1991-2020, 28°F
Shortest county season
191 days
NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze
Days to maturity
60 days
Growable Ground Plant Database

Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS and university Extension sources — per-field provenance varies and is published with the dataset.

Score your parcel · free

Your yard isn't the whole zone.

Indiana spans zones 5b-7b, but your yard sits in exactly one — and slope, tree cover, and cold-air pockets nudge it further. Enter your address and we'll score vietnamese coriander against your parcel's actual hardiness, soil, and sun.

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

No card required · your full report in seconds

Indiana is not one climate

Indiana’s winter-low ladder runs across 92 counties, from zone 5.5 in Benton County to zone 7 in Warrick County. That is 15°F between the two counties’ average coldest night — the difference between vietnamese coriander overwintering in the ground and coming under cover.

5.5 zonesBenton County7 zonesWarrick County

The middle half of 92 counties runs 66.5 zones, with a median of 6 zones — a 1.5-zone span end to end.

Measured across 92 Indiana counties. USDA PHZM 2023, per county. Quartiles are order statistics — every figure shown is a value a real county recorded, not an interpolation. Your own site sits somewhere inside this range; a parcel report resolves where.

Where Vietnamese Coriander Stands in Indiana

Vietnamese Coriander is rated for zones 911 — a cold floor USDA puts at 20 to 30°F. No Indiana county sits inside it, so in open ground this is a grown-under-cover plant here rather than a bed plant — which is a statement about Indiana winters, not about vietnamese coriander.

Below the zone 9 floor

92 counties

3 of 92 shown

Winter cold is the limit here — the same plant works in a container that comes under cover.

County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. A zone is a 10°F band of average annual extreme minimum temperature, so the floor above is the band the plant's rating denotes, not a single measured kill point. Slope, shelter and cold-air drainage routinely move a site half a zone either way from its county figure — which is the part only your address resolves.

Zone Comparison

Vietnamese Coriander Needs

  • USDA Zones: 9-11
  • Frost-Free Days: 120+
  • Sun: Part Sun
  • Mature size: 1.5 ft tall
  • Picking window: ~90 days of harvest
  • Drought tolerance: Low

Indiana Has

  • USDA Zones: 5b-7b
  • Last Hard Freeze (28°F): Apr 4 - Apr 9
  • First Hard Freeze (28°F): Oct 30 - Nov 4
  • Annual Rainfall: 36-46 inches
  • Common Soils: Silt loam, Clay loam, Glacial till

Plant Zone Range (zones 9-11)

9a
11b
3a (Cold)13b (Hot)

Preferred Soil pH

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

Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS, and university Extension sources — per-field provenance varies and is published with the dataset. State data: USDA ARS PHZM 2023, NOAA Climate Normals, NRCS SSURGO.

When to Plant Vietnamese Coriander in Indiana

The frost window

Across Indiana, the last spring hard freeze (28°F) clears between Apr 4 and Apr 9, and the first fall hard freeze lands between Oct 30 and Nov 4 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 204-day window you can count on — up to 214 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 vietnamese coriander goes out, not when it starts. It is sown under cover about 6 weeks ahead, so counting back from Indiana's late-side last freeze of Apr 9 is what fixes your sowing date — and a yard that clears frost earlier than the state's late date starts earlier still.

Winter standing

Indiana runs as cold as USDA zone 5, and no sourced winter-hardiness floor is on record for vietnamese coriander, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether vietnamese coriander is a permanent planting or a replant-every-spring crop for you turns on your own zone within Indiana; check its hardiness range against that before treating it as long-lived ground.

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

Frost window: NOAA Climate Normals 1991-2020. Plant timing fields: Growable Ground Plant Database — frost-free days from FAO ECOCROP, days to harvest from university Extension production guides, and growing-degree-day and chill-hour minimums that are compilation estimates rather than published figures. Your site's own frost dates can run earlier or later than the state range — a parcel report pins them down.

Growing Season Fit

The zone check says vietnamese coriander does not survive a Indiana winter in the ground. The season figures below measure a different question — whether it could finish a season here at all — and they only bear on Indiana under protection.

Frost-free days

Vietnamese Coriander wants 120+ frost-free days; a typical Indiana site sees ~209 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves comfortable headroom for succession planting.

Growing degree days

Vietnamese Coriander needs ~3000 GDD (base 50°F) to ripen. The state median runs ~3153 GDD (from PRISM 1991-2020 climate normals), so Indiana sits right at the threshold — pay attention to siting and microclimate.

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

Vietnamese Coriander likes near-neutral soil (pH 5.5-7.5). That's the common-ground band across Indiana's silt loam and clay loam — a soil test confirms it for your site. It will grow across that whole span, but it does best between pH 6 and 7 — worth knowing before you decide whether a Indiana soil test result is a problem or just a number. Drainage requirement: poorly (saturated >50% of year). A soil-survey lookup (NRCS SSURGO) flags whether your specific site matches.

Your land, not the state average

Indiana's soils run mostly silt loam, but SSURGO maps the series, texture, and drainage under your exact parcel. What matters for vietnamese coriander is the horizon its roots actually work, not the surface. That map unit, not the state average, decides how vietnamese coriander performs.

Check your parcel → Source: USDA NRCS SSURGO.

Plant pH requirements: FAO ECOCROP and USDA PLANTS, with the remaining rows from other published sources or Growable Ground compilation. Drainage: FAO ECOCROP, with the remaining rows from other published sources or Growable Ground compilation. Indiana soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.

Before you plant vietnamese coriander for food

Anything you grow to eat takes up what is in the ground it grows in, so what is on record near you is worth knowing before vietnamese coriander goes in. What follows is Indiana’s documented federal record at state scale — a screening signal, not a soil test, and not a statement about any one lot.

Safe to Grow Here?

What the federal record shows across Indiana — and how to grow with it.

Federal record: High

We checked the federal record across Indiana33,216 documented sites across 8 of the 9 source types we track.

The most significant on record: 423 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.

Indiana carries one of the heavier federal records we track — and that's not a verdict on your yard. Proximity to a documented site is information, not a diagnosis: nothing here says any particular parcel is affected. It does earn one concrete step — before food beds go in the ground, a professional soil test tells you exactly what you're working with, and raised beds with clean imported soil grow well almost anywhere in the meantime.

Know before you grow — the guide

Sources Checked

across Indiana

Severity Distribution

across Indiana

High147Moderate10,251Low22,818

Highest-Severity Sites

Superfund · Superfund NPL
PFAS Sampling · PFAS Detected
PFAS Sampling · PFAS Detected
PFAS Sampling · PFAS Detected
PFAS Sampling · PFAS Detected

A note from Gnorman

What an experienced grower watches for around here

In and around Indiana, two things run higher than the national average across Indiana — Toxics Release Inventory (2,883 sites) and Superfund (423 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.

Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.

Superfund: Superfund sites represent the most severe contamination in the federal system.

Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.

Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).

Sources: EPA, USGS1.8M documented sites tracked nationwide across 9 federal source types.

What Else to Consider for Vietnamese Coriander in Indiana

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

Heavy clay soils limit drainage in many areas

Late spring frosts through early May

Hot humid summers promote blight and mildew

Growing vietnamese coriander here specifically

Indiana's soils run mostly silt loam (Alfisols), and whether that suits vietnamese coriander'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 vietnamese coriander'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 Indiana grower, not just vietnamese coriander — is covered on the Indiana growing guide.

Timing shifts within Indiana

Indiana isn't one climate. In Steuben County, the last hard freeze (28°F) holds until about Apr 18 — roughly 11 days later than the recorded state median — so plant vietnamese coriander to your county's window, not the statewide date.

Vietnamese Coriander needs about 120 days of frost-free season to complete its cycle. Even Steuben County — Indiana’s shortest season at 191 frost-free days — clears that by 71 days, so season length isn’t the constraint anywhere in Indiana. What varies is your own parcel.

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"). Vietnamese Coriander's 120-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

Vietnamese Coriander draws honeybees (low value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, vietnamese coriander can only work that bloom inside Indiana's frost window — roughly 209 days, opening after the last 28°F freeze (Apr 4 - Apr 9) and closing at the first (Oct 30 - Nov 4), per NOAA Regional Climate Centers ACIS, 1991-2020.

Recommended Vietnamese Coriander Varieties for Indiana

Indiana publishes no state variety trial for vietnamese coriander, so we won't invent a "best for Indiana" list. Choose types rated to your USDA hardiness zone (5b-7b), and confirm winter survival and drainage against your own parcel.

Indiana Cooperative Extension

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

Is Vietnamese Coriander native to Indiana?

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

Looking for plants that belong here? The Indiana 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 Vietnamese Coriander in Indiana

When can I plant Vietnamese Coriander in Indiana?

Indiana's last spring hard freeze (28°F) clears between Apr 4 and Apr 9, and the first fall hard freeze lands between Oct 30 and Nov 4 (NOAA Regional Climate Centers ACIS, 1991-2020). No sourced winter-hardiness floor is on record for Vietnamese Coriander, so this page does not state whether it overwinters in Indiana and publishes no fall establishment date for it — check its hardiness range against your own zone before treating it as a permanent planting.

What hardiness zone is Vietnamese Coriander grown in across Indiana?

Indiana spans USDA hardiness zones 5b-7b (USDA ARS PHZM 2023). Vietnamese Coriander carries a range of zones 9-11, so the overlap zones are where outdoor growing is most reliable.

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

A typical Indiana site sees ~209 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Vietnamese Coriander needs 120+ 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 Steuben, the freeze-free season runs shorter than the state average, so verify your own county's window.

Is Vietnamese Coriander native to Indiana?

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

How should I amend the soil for Vietnamese Coriander in Indiana?

Vietnamese Coriander prefers pH 5.5-7.5 and poorly (saturated >50% of year) drainage (Growable Ground Plant Database). That sits in the common-ground band across Indiana soils — a 30-minute soil test from a local Extension lab confirms it for your specific site.

Will Vietnamese Coriander actually grow on my specific land in Indiana?

State-level zone + climate data is a sketch. A Growable Ground parcel report scores vietnamese coriander 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 Indiana

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

Three things about your lot that Indiana vietnamese coriander averages can't show:

Your soil pHYour frost-free days — Indiana averages 209Your sun & shade

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

25+ data sources read at your address, not the Indiana vietnamese coriander 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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