mountain laurel (Kalmia latifolia), photographi

Can I Grow Mountain Laurel in Indiana?

USDA Zones 5b-7b · Plant zone range 5-11

Yes — Strong Match

mountain laurel (zones 5-11) covers every zone Indiana contains (5b-7b), so hardiness is not what limits it anywhere in the state.

Mountain Laurel in Indiana — the short answer

Mountain Laurel in Indiana: hardy in zones 5–11, shade, against a state median of ~209 frost-free days.

Plant zones
5-11
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
Indiana zones
5b-7b
USDA PHZM 2023
Frost window
Apr 4 - Apr 9 – Oct 30 - Nov 4
NOAA RCC ACIS 1991-2020, 28°F
Shortest county season
191 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.

Indiana spans zones 5b-7b, but your yard sits in exactly one — and slope, tree cover, and cold-air pockets nudge it further. Enter your address and we'll score mountain laurel against your parcel's actual hardiness, soil, and sun.

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

Indiana is not one climate

Indiana’s winter-low ladder runs across 92 counties, from zone 5.5 in Benton County to zone 7 in Warrick County. That is 15°F between the two counties’ average coldest night — the difference between mountain laurel overwintering in the ground and coming under cover.

5.5 zonesBenton County7 zonesWarrick County

The middle half of 92 counties runs 66.5 zones, with a median of 6 zones — a 1.5-zone span end to end.

Measured across 92 Indiana counties. USDA PHZM 2023, per county. 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 in Indiana Fits Best

Even within Indiana's zones 5b-7b, county microclimates differ enough to change what thrives. These counties carry the closest zone match for mountain laurel (USDA PHZM 2023):

Zone Comparison

Mountain Laurel Needs

  • USDA Zones: 5-11
  • Frost-Free Days: 150+
  • Sun: Shade
  • Mature size: 10 ft tall
  • Drought tolerance: High

Indiana Has

  • USDA Zones: 5b-7b
  • Last Hard Freeze (28°F): Apr 4 - Apr 9
  • First Hard Freeze (28°F): Oct 30 - Nov 4
  • Annual Rainfall: 36-46 inches
  • Common Soils: Silt loam, Clay loam, Glacial till

Plant Zone Range (zones 5-11)

5a
11b
3a (Cold)13b (Hot)

Preferred Soil pH

3.5 (Acidic)7.0 (Neutral)9.0 (Alkaline)
Highlighted range: pH 4.55.5

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 Mountain Laurel in Indiana

The frost window

Across Indiana, the last spring hard freeze (28°F) clears between Apr 4 and Apr 9, and the first fall hard freeze lands between Oct 30 and Nov 4 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 204-day window you can count on — up to 214 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.

Winter standing

Indiana runs as cold as USDA zone 5, and no sourced winter-hardiness floor is on record for mountain laurel, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether mountain laurel is a permanent planting or a replant-every-spring crop for you turns on your own zone within Indiana; check its hardiness range against that before treating it as long-lived ground.

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 mountain laurel survives winter here. Whether the season is long enough — and warm enough — is a different question.

Frost-free days

Mountain Laurel wants 150+ frost-free days; a typical Indiana site sees ~209 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves a workable window — start indoors to bank time.

Chill hours

Mountain Laurel requires ~600 chill hours (32-45°F dormancy window). Indiana typically banks ~2500 chill hours per winter (from PRISM 1991-2020 climate normals), which keeps this plant on track.

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

Mountain Laurel prefers acidic soil (pH 4.5-5.5). Indiana's silt loam can run on the acidic side, which often aligns well — confirm with a soil test before planting.

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

What Else to Consider for Mountain Laurel in Indiana

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

Heavy clay soils limit drainage in many areas

Late spring frosts through early May

Hot humid summers promote blight and mildew

What to actually do about these — and the constraints that apply to every Indiana grower, not just mountain laurel — is covered on the Indiana growing guide.

Timing shifts within Indiana

Mountain Laurel needs about 150 days of frost-free season to complete its cycle. Even Steuben County — Indiana’s shortest season at 191 frost-free days — clears that by 41 days, so season length isn’t the constraint anywhere in Indiana. 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"). Mountain Laurel's 150-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

Mountain Laurel draws native bees (moderate value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, mountain laurel can only work that bloom inside Indiana's frost window — roughly 209 days, opening after the last 28°F freeze (Apr 4 - Apr 9) and closing at the first (Oct 30 - Nov 4), per NOAA Regional Climate Centers ACIS, 1991-2020.

Indiana Cooperative Extension

For Indiana-specific cultivar recommendations, planting calendars, and pest pressure for mountain laurel, the canonical source is Purdue Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.

Is Mountain Laurel native to Indiana?

Yes — the USDA PLANTS Database (accessed 2026-07-01) documents Mountain Laurel as native to Indiana. Planting it supports the pollinators and wildlife that evolved alongside it.

Native-range data: USDA PLANTS Database state-distribution records, accessed 2026-07-01.

Common Questions About Growing Mountain Laurel in Indiana

When can I plant Mountain Laurel in Indiana?

Indiana's last spring hard freeze (28°F) clears between Apr 4 and Apr 9, and the first fall hard freeze lands between Oct 30 and Nov 4 (NOAA Regional Climate Centers ACIS, 1991-2020). No sourced winter-hardiness floor is on record for Mountain Laurel, so this page does not state whether it overwinters in Indiana and publishes no fall establishment date for it — check its hardiness range against your own zone before treating it as a permanent planting.

What hardiness zone is Mountain Laurel grown in across Indiana?

Indiana spans USDA hardiness zones 5b-7b (USDA ARS PHZM 2023). Mountain Laurel carries a range of zones 5-11, so the overlap zones are where outdoor growing is most reliable.

How many frost-free days does a typical Indiana site have?

A typical Indiana site sees ~209 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Mountain Laurel needs 150+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date.

Is Mountain Laurel native to Indiana?

Yes — the USDA PLANTS Database (accessed 2026-07-01) documents Mountain Laurel as native to Indiana. Planting it supports the pollinators and wildlife that evolved alongside it.

How should I amend the soil for Mountain Laurel in Indiana?

Mountain Laurel prefers pH 4.5-5.5 (USDA PLANTS). Most Indiana soils run mildly acidic to neutral; many sites land near this band naturally, and a soil test plus targeted sulfur or organic amendment closes any gap.

Will Mountain Laurel actually grow on my specific land in Indiana?

State-level zone + climate data is a sketch. A Growable Ground parcel report scores mountain laurel 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 Indiana

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

Three things about your lot that Indiana mountain laurel averages can't show:

Your soil pHYour frost-free days — Indiana averages 209Your sun & shade

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

25+ data sources read at your address, not the Indiana mountain laurel average

Last updated: