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

Planting zone for 02873 — Rockville, RI

ZIP code 02873 (Rockville, Washington County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is May 3 and the first fall frost October 8.

Where ZIP 02873 is

Outlined: the ZIP code area · 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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostMay 3
First frostOct 8
2012 zone6b

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Rockville, RI…

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 Rockville, RI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 3median — 50% chance of a later frost
Safe for tender plantsMay 16only 10% chance of frost after
First fall frostOctober 8median — 10% chance by Sep 30
Growing season159 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 20 and returns around October 20.

From the NOAA station Kingston, RI — 12 miles away, elevation 118 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 02873

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 22 – Apr 5
SpinachSow outdoors · Mar 22 – Apr 12
Broccoli, cabbageStart indoors · Feb 22 – Mar 8
Broccoli, cabbageTransplant · Apr 12 – Apr 26
Onion setsPlant outdoors · Apr 5 – Apr 19
PotatoesPlant outdoors · Apr 12 – Apr 26
LettuceSow outdoors · Apr 5 – Apr 19
Carrots, beetsSow outdoors · Apr 12 – Apr 26
TomatoesStart indoors · Mar 8 – Mar 22
TomatoesTransplant · May 10 – May 24
Peppers, eggplantStart indoors · Feb 22 – Mar 8
Peppers, eggplantTransplant · May 17 – May 31
BeansSow outdoors · May 10 – May 24
Sweet cornSow outdoors · May 10 – May 24
Cucumbers, squashSow outdoors · May 10 – May 24
Fall lettuce, spinachSow outdoors · Aug 13 – Aug 27
GarlicPlant cloves · Sep 24 – Oct 29
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 3) and first fall frost (Oct 8) 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 02873 came on Apr 5 — about the same time as the 1991–2020 average (Apr 7).

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

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °FAmerican chestnut115 ft · blooms early summer · high shade tolerance · to −33 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Farborvitae50 ft · blooms mid spring · medium shade tolerance · to −33 °F

Shrubs 94

Allegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican holly40 ft · blooms mid spring · low shade tolerance · to −20 °FAmerican hornbeam30 ft · blooms mid spring · low shade tolerance · to −34 °F

Wildflowers & perennials 156

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine sweetvetch2 ft · blooms early summer · high shade tolerance · to −62 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °F

Grasses 125

American beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °FAtlantic mannagrass3 ft · blooms summer · low shade tolerance · to −8 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °Fbeaked spikerush3 ft · blooms late spring · high shade tolerance · to −28 °FBicknell's sedge3 ft · blooms late spring · low shade tolerance · to −38 °Fbig bluestem6 ft · blooms summer · high shade tolerance · to −46 °F

Vines 7

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °Ftrumpet creeper2 ft · blooms summer · high shade tolerance · to −13 °Ftrumpet honeysuckle16 ft · blooms late summer · low shade tolerance · to −33 °F

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 Rockville, RI.

Soil in Rockville, RI

The soil mapped at the center of ZIP 02873 is Woodbridge — moderately decomposed plant material, moderately well drained.

TextureModerately decomposed plant materialtop layer
DrainageModerately well drainednatural drainage class
Organic matter95%high
Hydrologic groupC/Dslow when drained; wet otherwise
Farmland classNot prime farmlandUSDA classification

Map unit: Woodbridge fine sandy loam, 0 to 8 percent slopes, extremely stony.

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 02873; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Rockville, RI

Summer high83 °Faverage high, July
Winter low21 °Faverage low, January
Hot days9days a year at 90 °F or more
Freezing nights128nights a year at 32 °F or less
Growing degree days2,865base 50 °F — the season’s usable heat
Longest day15 h 11 mindaylight on June 21
Shortest day9 h 10 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation50.9 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 40 °F, low 21 °F 40°21° JanFebruary: average high 43 °F, low 22 °F 43°22° FebMarch: average high 49 °F, low 28 °F 49°28° MarApril: average high 60 °F, low 37 °F 60°37° AprMay: average high 70 °F, low 47 °F 70°47° MayJune: average high 78 °F, low 56 °F 78°56° JunJuly: average high 83 °F, low 62 °F 83°62° JulAugust: average high 82 °F, low 60 °F 82°60° AugSeptember: average high 76 °F, low 53 °F 76°53° SepOctober: average high 65 °F, low 42 °F 65°42° OctNovember: average high 55 °F, low 34 °F 55°34° NovDecember: average high 45 °F, low 26 °F 45°26° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 4.41 in precipitation 4.4 JanFebruary: 3.36 in precipitation 3.4 FebMarch: 5.08 in precipitation 5.1 MarApril: 4.54 in precipitation 4.5 AprMay: 3.75 in precipitation 3.8 MayJune: 3.80 in precipitation 3.8 JunJuly: 3.46 in precipitation 3.5 JulAugust: 4.16 in precipitation 4.2 AugSeptember: 4.24 in precipitation 4.2 SepOctober: 4.31 in precipitation 4.3 OctNovember: 4.30 in precipitation 4.3 NovDecember: 5.46 in precipitation 5.5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Kingston, RI (12 mi away); precipitation: Richmond 4.6 Nne, RI (7 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

028326b
Hope Valley, RI · 3 mi
028336b
Hopkinton, RI · 3 mi
063846b
Voluntown, CT · 4 mi
028986b
Wyoming, RI · 6 mi
063596b
North Stonington, CT · 6 mi
028046b
Ashaway, RI · 7 mi
028126b
Carolina, RI · 7 mi
028946b
Wood River Junction, RI · 7 mi

Rhode Island planting zones →

Questions about 02873

What planting zone is ZIP code 02873?

ZIP code 02873 (Rockville, RI) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Rockville, RI?

The median last spring frost (32 °F) near 02873 is May 3; after May 16 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Kingston station.

When is the first frost in Rockville, RI?

The median first fall frost near 02873 is October 8, giving a median frost-free growing season of 159 days.

When should I plant tomatoes in 02873?

Start tomato seeds indoors around Mar 8 – Mar 22 and set transplants outside around May 10 – May 24, one to three weeks after the median last frost.

How much rain and snow does 02873 get?

About 50.9 inches of precipitation a year (NOAA 1991–2020 normals, Richmond 4.6 Nne station).

How hot do summers get in Rockville, RI?

The average high peaks at 83 °F in July, with about 9 days a year at 90 °F or more.

What kind of soil does 02873 have?

The USDA soil survey maps Woodbridge at the center of ZIP 02873: moderately decomposed plant material, moderately well drained.

Did spring come early in Rockville, RI in 2026?

Spring leaf-out near 02873 came on Apr 5 in 2026, about the same as the 1991–2020 average (Apr 7), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Rockville, RI?

Long-day onions: the longest day near 02873 is 15 h 11 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).