malanga (Xanthosoma sagittifolium), photographi

Can I Grow Malanga in Illinois?

USDA Zones 5a-7b · Plant zone range 9-12

Unlikely — Zone Mismatch

malanga (zones 9-12) does not overlap with Illinois's zone range (5a-7b). Growing outdoors is unlikely without significant protection.

2 zones short — what would close it

Malanga is hardy to zone 9, and the warmest ground in Illinois is zone 7 — 2 zones short. Planted in open ground it will not survive a Illinois winter. To grow it here, grow malanga 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 9-12 (plant) against 5-7 (Illinois). Lift modeled by crop_engine.GREENHOUSE_ZONE_MODIFIER_BY_SUBTYPE['earth_sheltered'] (+2.5 zones) via api/fast_sections.py Unlock Engine v2.

Malanga in Illinois — the short answer

Malanga in Illinois: hardy in zones 9–12, full sun, against a state median of ~212 frost-free days.

Plant zones
9-12
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
Illinois zones
5a-7b
USDA PHZM 2023
Frost window
Mar 29 - Apr 8 – Oct 28 - Nov 5
NOAA RCC ACIS 1991-2020, 28°F
Shortest county season
177 days
NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze
Days to maturity
270 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.

Illinois spans zones 5a-7b, but your yard has its own microclimate — slope, trees, and low spots shift frost and sun across a single parcel. Enter your address and we'll score malanga against your land's actual soil, sun, and frost.

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

Illinois is not one climate

A single Illinois answer averages 102 counties whose growing seasons are 67 days apart — from 177 frost-free days in Jo Daviess County to 244 in Alexander County. Which end of that your land sits nearer changes what malanga can finish before the first hard freeze.

177 daysJo Daviess County244 daysAlexander County

The middle half of 102 counties runs 203221 days, with a median of 212 days — a 67-day span end to end.

Measured across 102 Illinois counties. NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze. 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 Malanga Stands in Illinois

Malanga is rated for zones 912 — a cold floor USDA puts at 20 to 30°F. No Illinois 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 Illinois winters, not about malanga.

Below the zone 9 floor

102 counties

3 of 102 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

Malanga Needs

  • USDA Zones: 9-12
  • Frost-Free Days: 120+
  • Sun: Full Sun
  • Mature size: 5 ft tall
  • Picking window: ~30 days of harvest
  • Drought tolerance: Low

Illinois Has

  • USDA Zones: 5a-7b
  • Last Hard Freeze (28°F): Mar 29 - Apr 8
  • First Hard Freeze (28°F): Oct 28 - Nov 5
  • Annual Rainfall: 34-48 inches
  • Common Soils: Prairie loam, Silt loam, Clay loam

Plant Zone Range (zones 9-12)

9a
12b
3a (Cold)13b (Hot)

Preferred Soil pH

3.5 (Acidic)7.0 (Neutral)9.0 (Alkaline)
Highlighted range: pH 4.57.8

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 Malanga in Illinois

The frost window

Across Illinois, the last spring hard freeze (28°F) clears between Mar 29 and Apr 8, and the first fall hard freeze lands between Oct 28 and Nov 5 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 203-day window you can count on — up to 221 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.

Frost tenderness

Malanga is frost-tender — FAO ECOCROP puts its killing temperature at 32°F — so set plants out two to three weeks PAST your local last hard freeze, not on it and not on the state's earliest date. The 28°F marker above is when killing freezes stop, not when light frost does. That is the point where cold damages growing tissue, not a winter-survival floor — an established perennial comes through far colder while dormant, which is what its hardiness zone tells you.

Days to maturity vs. the window

At 270 days to maturity (Growable Ground Plant Database), even Illinois's kindest 221-day season runs short — challenging without season extension. An indoor start plus row cover on both shoulders of the season closes the gap.

Timing tuned to sub-state frost dates — Jo Daviess 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 malanga does not survive a Illinois 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 Illinois under protection.

Frost-free days

Malanga wants 120+ frost-free days; a typical Illinois site sees ~212 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves comfortable headroom for succession planting.

Growing degree days

Malanga needs ~4000 GDD (base 50°F) to ripen. The state median runs ~3352 GDD (from PRISM 1991-2020 climate normals), so Illinois's typical season runs short on heat — pick a south-facing site and consider season extension.

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

Malanga tolerates a wide pH range (pH 4.5-7.8) — 3.3 units, acid ground through alkaline — so soil acidity is rarely what limits it in Illinois. A soil test is still worth having, but for what else it tells you about this site, not to clear this plant. It will grow across that whole span, but it does best between pH 5.5 and 7 — worth knowing before you decide whether a Illinois soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Illinois site is heavier clay or sits in a low spot, raised beds or amendment with compost solve it.

Your land, not the state average

Whether malanga is safe to eat from Illinois soil is a block-by-block question, not a town-wide one — 52,971 documented contamination sites mean levels spike on some parcels and not the one next door. Malanga roots to about 19 inches, so it is the top 19 inches under your address that decide what it takes up, so only a test on your address settles it.

Check your parcel → Source: USDA NRCS SSURGO + EPA/state contamination databases.

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. Illinois soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.

Before you plant malanga 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 malanga goes in. What follows is Illinois’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 Illinois — and how to grow with it.

Federal record: High

We checked the federal record across Illinois52,971 documented sites across 8 of the 9 source types we track.

The most significant on record: 622 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.

Illinois 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 Illinois

Severity Distribution

across Illinois

High513Moderate12,353Low40,105

Highest-Severity Sites

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

A note from Gnorman

What an experienced grower watches for around here

In and around Illinois, two things run higher than the national average across Illinois — PFAS (482 sites) and Toxics Release Inventory (3,504 sites). That's not a problem with your land — it's information about it.

PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.

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

Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.

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

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

What Else to Consider for Malanga in Illinois

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

Heavy clay soils in northern IL drain poorly

Extreme temperature swings between summer and winter

Japanese beetles are a major garden pest

Growing malanga here specifically

Because you eat the root of malanga that sit in the soil, contamination matters more than for most crops — Illinois has 52,971 documented sites, and lead concentrates block by block, not town-wide.

Test your soil for lead first, and raise malanga in clean imported soil if the reading is high. How to handle it →

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

Timing shifts within Illinois

Illinois isn't one climate. In Jo Daviess County, the last hard freeze (28°F) holds until about Apr 22 — roughly 20 days later than the recorded state median — so plant malanga to your county's window, not the statewide date.

Malanga needs about 120 days of frost-free season to complete its cycle. Even Jo Daviess County — Illinois’s shortest season at 177 frost-free days — clears that by 57 days, so season length isn’t the constraint anywhere in Illinois. What varies is your own parcel.

Across Illinois’s 102 counties the frost-free season runs from 177 days in Jo Daviess County to 244 days in Alexander County — a spread of 67 days, which is why a single statewide planting date misleads. The median Illinois county sees 212 frost-free days, leaving malanga about 92 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"). Malanga's 120-day requirement: USDA PLANTS / Growable Ground plant database (minimum frost-free days). A parcel report resolves your address's own frost dates.

Good to Know Before You Plant Malanga

Malanga is listed as toxic to dogs, cats (all) at a moderate level (ASPCA). Most listed plants only cause brief upset — a raised bed or a fenced corner usually keeps curious pets clear. Worth knowing for placement: in Illinois this is a one-season plant and the first hard freeze (Oct 28 - Nov 5) takes it down, so the exposure above is a summer-long one rather than something standing in the bed all year.

Illinois Cooperative Extension

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

Is Malanga native to Illinois?

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

Looking for plants that belong here? The Illinois 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 Malanga in Illinois

When can I plant Malanga in Illinois?

Illinois's last spring hard freeze (28°F) clears between Mar 29 and Apr 8, and the first fall hard freeze lands between Oct 28 and Nov 5 (NOAA Regional Climate Centers ACIS, 1991-2020). Malanga is frost-tender — its killing temperature is 32°F (FAO ECOCROP — the point where cold damages growing tissue, not a winter-survival floor) — so wait two to three weeks past your site's last hard freeze, when light frost has also stopped, before planting out.

Can Malanga mature before first frost in Illinois?

Malanga needs 270 days to mature (Growable Ground Plant Database), and even Illinois's longest typical season runs 221 days (NOAA Regional Climate Centers ACIS, 1991-2020) — challenging without season extension. An indoor start plus row cover on both season shoulders closes the gap.

What hardiness zone is Malanga grown in across Illinois?

Illinois spans USDA hardiness zones 5a-7b (USDA ARS PHZM 2023). Malanga carries a range of zones 9-12, so the overlap zones are where outdoor growing is most reliable.

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

A typical Illinois site sees ~212 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Malanga 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 Jo Daviess, the freeze-free season runs shorter than the state average, so verify your own county's window.

Is Malanga native to Illinois?

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

How should I amend the soil for Malanga in Illinois?

Malanga tolerates pH 4.5-7.8 and well (dry spells) drainage (FAO ECOCROP). That is a 3.3-unit span, acid ground through alkaline, so pH is rarely what limits this plant on a Illinois site — amend for drainage and organic matter first.

Will Malanga actually grow on my specific land in Illinois?

State-level zone + climate data is a sketch. A Growable Ground parcel report scores malanga 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 Illinois

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

Three things about your lot that Illinois malanga averages can't show:

Your soil pHYour frost-free days — Illinois averages 212Your sun & shade

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

25+ data sources read at your address, not the Illinois malanga 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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