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

Planting zone for 46268 — Indianapolis, IN

ZIP code 46268 (Indianapolis, Marion County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 12 and the first fall frost October 29.

Where ZIP 46268 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.

Zone6a−10 to −5 °F
Coldest night−23.3 to −20.6 °C
Last frostApr 12
First frostOct 29
2012 zone6a

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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Indianapolis, IN…

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 Indianapolis, IN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 12median — 50% chance of a later frost
Safe for tender plantsApril 29only 10% chance of frost after
First fall frostOctober 29median — 10% chance by Oct 16
Growing season198 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 1 and returns around November 6.

From the NOAA station Indianapolis Eagle Creek Airport, IN — 6 miles away, elevation 824 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 46268

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 1 – Mar 15
SpinachSow outdoors · Mar 1 – Mar 22
Broccoli, cabbageStart indoors · Feb 1 – Feb 15
Broccoli, cabbageTransplant · Mar 22 – Apr 5
Onion setsPlant outdoors · Mar 15 – Mar 29
PotatoesPlant outdoors · Mar 22 – Apr 5
LettuceSow outdoors · Mar 15 – Mar 29
Carrots, beetsSow outdoors · Mar 22 – Apr 5
TomatoesStart indoors · Feb 15 – Mar 1
TomatoesTransplant · Apr 19 – May 3
Peppers, eggplantStart indoors · Feb 1 – Feb 15
Peppers, eggplantTransplant · Apr 26 – May 10
BeansSow outdoors · Apr 19 – May 3
Sweet cornSow outdoors · Apr 19 – May 3
Cucumbers, squashSow outdoors · Apr 19 – May 3
Fall lettuce, spinachSow outdoors · Sep 3 – Sep 17
GarlicPlant cloves · Oct 15 – Nov 19
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 12) and first fall frost (Oct 29) 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 46268 came on Mar 10 — 16 days earlier than the 1991–2020 average (Mar 26).

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 6a in Indiana

558 plants native to the lower 48 states, recorded in Indiana, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 71

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 105

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny 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 °F

Wildflowers & perennials 200

American 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 lotus3 ft · blooms mid summer · high shade tolerance · to −36 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °FAmerican speedwell0.8 ft · blooms mid summer · low shade tolerance · to −38 °F

Grasses 161

American beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °Farctic brome3 ft · blooms early summer · low shade tolerance · to −33 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °Fbeaked spikerush3 ft · blooms late spring · high shade tolerance · to −28 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °FBicknell's sedge3 ft · blooms late spring · low shade tolerance · to −38 °F

Vines 9

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fcatbird grape30 ft · blooms late spring · medium shade tolerance · to −13 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Ffrost grape83 ft · blooms late spring · medium shade tolerance · to −23 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °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 Indianapolis, IN.

Soil in Indianapolis, IN

The soil mapped at the center of ZIP 46268 is Miami — silt loam, moderately well drained.

TextureSilt loama good balance for most vegetables
pH6.5neutral; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter2%moderate
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Miami silt loam-Urban land complex, 2 to 6 percent slopes, eroded.

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 46268; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Indianapolis, IN

Summer high85 °Faverage high, July
Winter low21 °Faverage low, January
Hot days17days a year at 90 °F or more
Freezing nights106nights a year at 32 °F or less
Growing degree days3,703base 50 °F — the season’s usable heat
Longest day15 h 00 mindaylight on June 21
Shortest day9 h 20 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation42.1 inper year, rain and melted snow
Snowfall17 inper year

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 36 °F, low 21 °F 36°21° JanFebruary: average high 41 °F, low 24 °F 41°24° FebMarch: average high 52 °F, low 33 °F 52°33° MarApril: average high 64 °F, low 43 °F 64°43° AprMay: average high 74 °F, low 54 °F 74°54° MayJune: average high 82 °F, low 63 °F 82°63° JunJuly: average high 85 °F, low 67 °F 85°67° JulAugust: average high 84 °F, low 65 °F 84°65° AugSeptember: average high 78 °F, low 57 °F 78°57° SepOctober: average high 66 °F, low 45 °F 66°45° OctNovember: average high 52 °F, low 35 °F 52°35° NovDecember: average high 41 °F, low 26 °F 41°26° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 2.93 in precipitation, 8.2 in snowfall 2.9❄8 JanFebruary: 2.19 in precipitation, 3.3 in snowfall 2.2❄3 FebMarch: 3.17 in precipitation, 1.5 in snowfall 3.2❄2 MarApril: 4.55 in precipitation, 0.1 in snowfall 4.5 AprMay: 4.68 in precipitation 4.7 MayJune: 4.74 in precipitation 4.7 JunJuly: 3.98 in precipitation 4.0 JulAugust: 3.30 in precipitation 3.3 AugSeptember: 3.21 in precipitation 3.2 SepOctober: 3.26 in precipitation, 0.1 in snowfall 3.3 OctNovember: 3.37 in precipitation, 0.4 in snowfall 3.4 NovDecember: 2.68 in precipitation, 3.6 in snowfall 2.7❄4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Indianapolis Eagle Creek Airport, IN (6 mi away); precipitation: Indianapolis Eagle Creek 4 Nne, IN (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

3 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

462606a
Indianapolis, IN · 3 mi
462786a
Indianapolis, IN · 3 mi
462286b
Indianapolis, IN · 4 mi
462546b
Indianapolis, IN · 4 mi
462886b
Indianapolis, IN · 5 mi
462906a
Indianapolis, IN · 5 mi
460326a
Carmel, IN · 6 mi
462806a
Indianapolis, IN · 6 mi

All 56 ZIP codes in Indianapolis → · Indiana planting zones →

Questions about 46268

What planting zone is ZIP code 46268?

ZIP code 46268 (Indianapolis, IN) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).

When is the last frost in Indianapolis, IN?

The median last spring frost (32 °F) near 46268 is April 12; after April 29 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Indianapolis Eagle Creek Airport station.

When is the first frost in Indianapolis, IN?

The median first fall frost near 46268 is October 29, giving a median frost-free growing season of 198 days.

When should I plant tomatoes in 46268?

Start tomato seeds indoors around Feb 15 – Mar 1 and set transplants outside around Apr 19 – May 3, one to three weeks after the median last frost.

How much rain and snow does 46268 get?

About 42.1 inches of precipitation a year and 17 inches of snowfall (NOAA 1991–2020 normals, Indianapolis Eagle Creek 4 Nne station).

How hot do summers get in Indianapolis, IN?

The average high peaks at 85 °F in July, with about 17 days a year at 90 °F or more.

What kind of soil does 46268 have?

The USDA soil survey maps Miami at the center of ZIP 46268: silt loam, moderately well drained, pH about 6.5 (neutral).

Did spring come early in Indianapolis, IN in 2026?

Spring leaf-out near 46268 came on Mar 10 in 2026, 16 days earlier than the 1991–2020 average (Mar 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Indianapolis, IN?

Long-day onions: the longest day near 46268 is 15 h 00 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).