phasey bean (Macroptilium lathyroides), photographi

Can I Grow Phasey Bean in Illinois?

USDA Zones 5a-7b · Plant zone range 9-13

Unlikely — Zone Mismatch

phasey bean (zones 9-13) does not overlap with Illinois's zone range (5a-7b). Growing outdoors is unlikely without significant protection.

2 zones short — what would close it

Phasey Bean 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 phasey bean 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 9-13 (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.

Phasey Bean in Illinois — the short answer

Phasey Bean in Illinois: hardy in zones 9–13, full sun, against a state median of ~212 frost-free days.

Plant zones
9-13
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

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.

Phasey Bean is grown as an annual, so your winter zone isn't the deciding factor — your frost-free window is. A typical Illinois site runs ~212 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 phasey bean 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.

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 phasey bean 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 Phasey Bean Stands in Illinois

Phasey Bean is rated for zones 913 — 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 phasey bean.

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

Phasey Bean Needs

  • USDA Zones: 9-13
  • Frost-Free Days: 90+
  • Sun: Full Sun
  • Mature size: 3 ft tall
  • Drought tolerance: Medium

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 9-13)

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

Preferred Soil pH

3.5 (Acidic)7.0 (Neutral)9.0 (Alkaline)
Highlighted range: pH 4.58.0

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 Phasey Bean 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.

When to start the seed

Phasey Bean is direct-sown where it grows rather than started under cover, so there is no seed-tray head start to bank — Illinois's dates above are the whole calendar for it. That makes the last-freeze date the binding constraint, and a warmer pocket of your own yard is worth more to this crop than it is to a transplanted one.

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 phasey bean 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

Phasey Bean wants 90+ frost-free days; a typical Illinois site sees ~212 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves comfortable headroom for succession planting.

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

Phasey Bean tolerates a wide pH range (pH 4.5-8) — 3.5 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 6 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 poorly (saturated >50% of year), 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

SSURGO maps about 52.0% of Illinois as poorly or somewhat-poorly drained, and the class flips parcel to parcel. Phasey Bean sits mid-range for drought tolerance, so either extreme can cost you — your soil map unit, not the state average, is the real answer.

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

What Else to Consider for Phasey Bean 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 phasey bean here specifically

Phasey Bean needs sharp drainage and sends shallow roots; its growing tissue takes cold to about 30°F (FAO ECOCROP), but in Illinois, about 52.0% of soils are poorly-drained (SSURGO), and standing water is what actually kills it.

Build phasey bean up on a coarse, free-draining mound so its roots never sit in saturated soil. How to handle it →

What to actually do about these — and the constraints that apply to every Illinois grower, not just phasey bean — 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 phasey bean to your county's window, not the statewide date.

Phasey Bean needs about 90 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 87 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 phasey bean about 122 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"). Phasey Bean's 90-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

Phasey Bean draws honeybees and native bees (moderate value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, phasey bean can only work that bloom inside Illinois's frost window — roughly 212 days, opening after the last 28°F freeze (Mar 29 - Apr 8) and closing at the first (Oct 28 - Nov 5), per NOAA Regional Climate Centers ACIS, 1991-2020.

Illinois Cooperative Extension

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

Is Phasey Bean native to Illinois?

No — the USDA PLANTS Database lists Phasey Bean 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 Phasey Bean in Illinois

When can I plant Phasey Bean 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). 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.

What hardiness zone is Phasey Bean grown in across Illinois?

Illinois spans USDA hardiness zones 5a-7b (USDA ARS PHZM 2023). Phasey Bean carries a range of zones 9-13, 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). Phasey Bean needs 90+ 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 Phasey Bean native to Illinois?

No — the USDA PLANTS Database lists Phasey Bean 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 Phasey Bean in Illinois?

Phasey Bean tolerates pH 4.5-8 and poorly (saturated >50% of year), well (dry spells) drainage (FAO ECOCROP). That is a 3.5-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 Phasey Bean actually grow on my specific land in Illinois?

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

Three things about your lot that Illinois phasey bean 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 phasey bean average

Explore More

Explore Illinois county by county

Illinois carries 102 counties with their own USDA zone — a sample of the growing pages for phasey bean there:

Where else phasey bean grows

Phasey Bean's zone band crosses state lines — these are the states closest to Illinois in winter climate where it also has a page, plus the far ends of its range. Each one re-answers the question with that state's own record.

More to grow in Illinois

Illinois has a growing page for 893 plants — a rotating sample of the rest of the shelf.

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

Last updated: