Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for Cranston, RI

Cranston, RI is in USDA zones 6b to 7a across its 3 ZIP codes. The median last spring frost is April 11 and the first fall frost October 30.

Cranston on the zone map

Outlined: its 3 ZIP code areas · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zones6b–7a−5 to 5 °F
ZIP codes3
Last frostApr 11
First frostOct 30
Growing season199 days

6b 1 ZIP   7a 2 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

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Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in Cranston, RI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 11median — 50% chance of a later frost
Safe for tender plantsApril 23only 10% chance of frost after
First fall frostOctober 30median — 10% chance by Oct 16
Growing season199 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 1 and returns around November 9.

From the NOAA station Providence T F Green Airport, RI, elevation 59 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in Cranston

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 28 – Mar 14
SpinachSow outdoors · Feb 28 – Mar 21
Broccoli, cabbageStart indoors · Jan 31 – Feb 14
Broccoli, cabbageTransplant · Mar 21 – Apr 4
Onion setsPlant outdoors · Mar 14 – Mar 28
PotatoesPlant outdoors · Mar 21 – Apr 4
LettuceSow outdoors · Mar 14 – Mar 28
Carrots, beetsSow outdoors · Mar 21 – Apr 4
TomatoesStart indoors · Feb 14 – Feb 28
TomatoesTransplant · Apr 18 – May 2
Peppers, eggplantStart indoors · Jan 31 – Feb 14
Peppers, eggplantTransplant · Apr 25 – May 9
BeansSow outdoors · Apr 18 – May 2
Sweet cornSow outdoors · Apr 18 – May 2
Cucumbers, squashSow outdoors · Apr 18 – May 2
Fall lettuce, spinachSow outdoors · Sep 4 – Sep 18
GarlicPlant cloves · Oct 16 – Nov 20
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 11) and first fall frost (Oct 30) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 02920 came on Apr 2 — about the same time as the 1991–2020 average (Apr 2).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 6b in Rhode Island

452 plants native to the lower 48 states, recorded in Rhode Island, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. Each links to its USDA PLANTS profile.

Trees 56

Shrubs 94

Wildflowers & perennials 156

Grasses 125

Vines 7

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Cranston, RI.

Soil in Cranston, RI

The soil mapped at the center of ZIP 02920 is Paxton — fine sandy loam, well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding
pH5.5moderately acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter5.5%high
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Paxton-Urban land complex, 3 to 15 percent slopes.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 02920; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Cranston, RI

Summer high84 °Faverage high, July
Winter low22 °Faverage low, January
Hot days12days a year at 90 °F or more
Freezing nights109nights a year at 32 °F or less
Growing degree days3,090base 50 °F — the season’s usable heat
Longest day15 h 13 mindaylight on June 21
Shortest day9 h 08 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation47.5 inper year, rain and melted snow
Snowfall37 inper year; 25 days with snow on the ground

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 38 °F, low 22 °F 38°22° JanFebruary: average high 41 °F, low 24 °F 41°24° FebMarch: average high 48 °F, low 30 °F 48°30° MarApril: average high 59 °F, low 40 °F 59°40° AprMay: average high 69 °F, low 49 °F 69°49° MayJune: average high 78 °F, low 59 °F 78°59° JunJuly: average high 84 °F, low 65 °F 84°65° JulAugust: average high 82 °F, low 64 °F 82°64° AugSeptember: average high 75 °F, low 57 °F 75°57° SepOctober: average high 64 °F, low 45 °F 64°45° OctNovember: average high 53 °F, low 36 °F 53°36° NovDecember: average high 43 °F, low 28 °F 43°28° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 3.96 in precipitation, 10.3 in snowfall 4.0❄10 JanFebruary: 3.44 in precipitation, 10.5 in snowfall 3.4❄11 FebMarch: 4.90 in precipitation, 6.4 in snowfall 4.9❄6 MarApril: 4.29 in precipitation, 0.6 in snowfall 4.3❄1 AprMay: 3.37 in precipitation 3.4 MayJune: 3.81 in precipitation 3.8 JunJuly: 2.91 in precipitation 2.9 JulAugust: 3.59 in precipitation 3.6 AugSeptember: 4.17 in precipitation 4.2 SepOctober: 4.18 in precipitation, 0.2 in snowfall 4.2 OctNovember: 4.27 in precipitation, 1 in snowfall 4.3❄1 NovDecember: 4.65 in precipitation, 7.6 in snowfall 4.7❄8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Providence T F Green Airport, RI (4 mi away); precipitation: Providence T F Green Airport, RI (4 mi away). Daylight is calculated from latitude.

ZIP codes in Cranston

Rhode Island planting zones →

Questions about Cranston

What planting zone is Cranston, RI?

Cranston, RI is in USDA hardiness zones 6b to 7a on the 2023 map (6b: −5 to 0 °F; 7a: 0 to 5 °F).

When is the last frost in Cranston, RI?

The median last spring frost is April 11 and the median first fall frost is October 30 (NOAA 1991–2020 normals, Providence T F Green Airport station).

When can I plant a garden in Cranston, RI?

Cool-season crops like peas and spinach go in around Feb 28 – Mar 21; tomatoes, peppers, beans and squash after about Apr 18, once frost risk has passed.

What kind of onions grow in Cranston, RI?

Long-day onions: the longest day is 15 h 13 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

How much rain and snow does Cranston, RI get?

About 47.5 inches of precipitation a year and 37 inches of snowfall (NOAA 1991–2020 normals).