jicama (Pachyrhizus erosus), photographi

Can I Grow Jicama in Rhode Island?

USDA Zones 6b-7b · Plant zone range 9-12

Unlikely — Zone Mismatch

jicama (zones 9-12) does not overlap with Rhode Island's zone range (6b-7b). Growing outdoors is unlikely without significant protection.

2 zones short — what would close it

Jicama is hardy to zone 9, and the warmest ground in Rhode Island is zone 7 — 2 zones short. Planted in open ground it will not survive a Rhode Island winter. To grow it here, grow jicama 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 6-7 (Rhode Island). Lift modeled by crop_engine.GREENHOUSE_ZONE_MODIFIER_BY_SUBTYPE['earth_sheltered'] (+2.5 zones) via api/fast_sections.py Unlock Engine v2.

Jicama in Rhode Island — the short answer

Jicama in Rhode Island: hardy in zones 9–12, full sun, against a state median of ~225 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
Rhode Island zones
6b-7b
USDA PHZM 2023
Frost window
Mar 27 - Apr 3 – Nov 7 - Nov 21
NOAA RCC ACIS 1991-2020, 28°F
Shortest county season
210 days
NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze
Days to maturity
150 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.

Rhode Island spans zones 6b-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 jicama 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

Where Jicama Stands in Rhode Island

Jicama is rated for zones 912 — a cold floor USDA puts at 20 to 30°F. No Rhode Island 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 Rhode Island winters, not about jicama.

Below the zone 9 floor

5 counties

3 of 5 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

Jicama Needs

  • USDA Zones: 9-12
  • Sun: Full Sun
  • Mature size: 15 ft tall
  • Picking window: ~45 days of harvest
  • Drought tolerance: Medium

Rhode Island Has

  • USDA Zones: 6b-7b
  • Last Hard Freeze (28°F): Mar 27 - Apr 3
  • First Hard Freeze (28°F): Nov 7 - Nov 21
  • Annual Rainfall: 44-52 inches
  • Common Soils: Glacial till, Sandy loam, Coastal sand

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 4.38.0

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 Jicama in Rhode Island

The frost window

Across Rhode Island, the last spring hard freeze (28°F) clears between Mar 27 and Apr 3, and the first fall hard freeze lands between Nov 7 and Nov 21 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 218-day window you can count on — up to 239 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 jicama goes out, not when it starts. It is sown under cover about 4 weeks ahead, so counting back from Rhode Island's late-side last freeze of Apr 3 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 150 days to maturity (Growable Ground Plant Database), counting from the last hard freeze it ripens with 68 days to spare even in Rhode Island's tightest freeze scenario — room for a later start or a second sowing.

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 jicama does not survive a Rhode Island 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 Rhode Island under protection.

Days to maturity

Jicama matures in ~150 days (Growable Ground Plant Database). A typical Rhode Island site has ~225 frost-free days, so plenty of room for a second succession.

Growing degree days

Jicama needs ~3500 GDD (base 50°F) to ripen. The state median runs ~2635 GDD (from PRISM 1991-2020 climate normals), so Rhode Island'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

Jicama tolerates a wide pH range (pH 4.3-8) — 3.7 units, acid ground through alkaline — so soil acidity is rarely what limits it in Rhode Island. 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 6.5 and 8 — worth knowing before you decide whether a Rhode Island soil test result is a problem or just a number.

Your land, not the state average

Rhode Island's soils run mostly fine sandy loam, but SSURGO maps the series, texture, and drainage under your exact parcel. Jicama needs about 59 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 jicama 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. Rhode Island soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.

Before you plant jicama 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 jicama goes in. What follows is Rhode Island’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 Rhode Island — and how to grow with it.

Federal record: High

We checked the federal record across Rhode Island7,250 documented sites across 7 of the 9 source types we track.

The most significant on record: 141 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.

Rhode Island 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 Rhode Island

Severity Distribution

across Rhode Island

High26Moderate1,842Low5,382

Highest-Severity Sites

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

A note from Gnorman

What an experienced grower watches for around here

In and around Rhode Island, two things run higher than the national average across Rhode Island — Superfund (141 sites) and Toxics Release Inventory (446 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.

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

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

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

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 Jicama in Rhode Island

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

Small lot sizes limit garden space in much of the state

Salt spray affects coastal plantings

Rocky glacial soils need clearing

Growing jicama here specifically

Rhode Island's soils run mostly fine sandy loam (Inceptisols), and whether that suits jicama's pH 4.3–8.0 preference comes down to your exact parcel, not the statewide picture.

Pull your parcel's SSURGO map unit, test pH, and amend toward jicama's 4.3–8.0 target before planting. How to handle it →

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

Timing shifts within Rhode Island

Jicama needs about 150 days of frost-free season from planting to harvest. Even Providence County — Rhode Island’s shortest season at 210 frost-free days — clears that by 60 days, so season length isn’t the constraint anywhere in Rhode Island. 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"). Jicama's 150-day requirement: USDA PLANTS / Growable Ground plant database (days to maturity). A parcel report resolves your address's own frost dates.

Pollinator + Wildlife Value

Jicama draws honeybees and native bees (moderate value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, jicama can only work that bloom inside Rhode Island's frost window — roughly 225 days, opening after the last 28°F freeze (Mar 27 - Apr 3) and closing at the first (Nov 7 - Nov 21), per NOAA Regional Climate Centers ACIS, 1991-2020.

Rhode Island Cooperative Extension

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

Is Jicama native to Rhode Island?

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

Looking for plants that belong here? The Rhode Island 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 Jicama in Rhode Island

When can I plant Jicama in Rhode Island?

Rhode Island's last spring hard freeze (28°F) clears between Mar 27 and Apr 3, and the first fall hard freeze lands between Nov 7 and Nov 21 (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 Jicama mature before first frost in Rhode Island?

Yes — Jicama matures in 150 days (Growable Ground Plant Database), and Rhode Island's dependable hard-freeze-free window runs 218 days (NOAA Regional Climate Centers ACIS, 1991-2020), leaving 68 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 Jicama grown in across Rhode Island?

Rhode Island spans USDA hardiness zones 6b-7b (USDA ARS PHZM 2023). Jicama 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 Rhode Island site have?

A typical Rhode Island site sees ~225 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Jicama should be matched against that window, so check whether your local microclimate runs above or below the state average before settling on a planting date.

Is Jicama native to Rhode Island?

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

How should I amend the soil for Jicama in Rhode Island?

Jicama tolerates pH 4.3-8 (FAO ECOCROP). That is a 3.7-unit span, acid ground through alkaline, so pH is rarely what limits this plant on a Rhode Island site — amend for drainage and organic matter first.

Will Jicama actually grow on my specific land in Rhode Island?

State-level zone + climate data is a sketch. A Growable Ground parcel report scores jicama 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 Rhode Island

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

Three things about your lot that Rhode Island jicama averages can't show:

Your soil pHYour frost-free days — Rhode Island averages 225Your sun & shade

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

25+ data sources read at your address, not the Rhode Island jicama 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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