What USDA hardiness zone is Montgomery County, Indiana?

Montgomery County, Indiana spans USDA hardiness zones 5b to 6a. 60% of its ZIP codes are zone 6a, so there is no single zone for the county.

When is the last spring frost in Montgomery County, Indiana?

The median last spring freeze runs April 20 – April 30 across the 4 NOAA weather stations serving Montgomery County, Indiana, from NOAA 1991-2020 Climate Normals. Half of years freeze later than the median.

Indiana

Planting zones in Montgomery County, Indiana

This county spans USDA zones 5b to 6a, so there is no single zone for Montgomery County and anyone who gives you one is rounding. 60% of its ZIP codes are zone 6a; the rest are not.

USDA zones 5b–6a 2 zones across 10 ZIP codes

ZIP codes 10 10 have a NOAA station within range

Weather stations 4 NOAA 1991–2020 normals, across 505 sq mi

Your ZIP code

Get the exact answer for your address

Everything above describes Montgomery County, Indiana as a whole. Hardiness zones and freeze dates are published per ZIP code, so yours is exact — enter it and this page will tell you your zone, which NOAA station it comes from and how far away that station is.

The growing season in Montgomery County is closing

Nothing in the 32-crop table still has time to mature here. The first fall freeze normally arrives October 12 – October 20 across the 4 NOAA stations serving this county .

Your next season already has a date

The first job of it is 🧅 Green Onions, start indoors, around February 23 – March 5 — counted back from a last spring freeze of April 20 – April 30 here.

Every spring date for your ZIP →

These are ranges across the whole county. The ZIP lookup above gives the dates from your own nearest station instead.

All 4 stations agreeAt least one station

Every one of the 4 NOAA stations serving this county counts April 30 – October 12 as growing season (165 days). Widening to any single station gives April 20 – October 20 (183 days).

Which zone you are in depends where you are

Montgomery County covers 2 hardiness zones. A guide that gives the county one zone has picked whichever is largest and rounded everyone else into it — fine for the 60% in zone 6a and wrong for the other 40%. Here is the actual split.

Zone	ZIP codes	Share
6a	6	60%
5b	4	40%

Zones are published per ZIP code, so yours is exact even though the county's is not. The hardiness tool will tell you which one you are in.

Your freeze dates

Last spring freeze April 20 – April 30

First fall freeze October 12 – October 20

Across the 4 NOAA stations serving this county. These are medians — half of years freeze later than the date shown — so treat the later end of each range as the cautious one.

The growing season runs 164–182 days depending which station you are nearest, as published by NOAA rather than computed from the dates above. Summer highs average 81.7–84.6 °F in June–August. Summer rain over the same months runs 12.9–14.0" across those 4 stations, against the rough inch a week — about 13 inches over the same 92 days — that a vegetable garden is usually reckoned to want. At the middle station that is covered, so watering in Montgomery County is for the gaps between storms rather than the whole season. The inches are NOAA's published normals; the inch a week is a rule of thumb, and it takes no account of a 83 °F summer afternoon drying the soil faster than a cool one.

Every ZIP code in Montgomery County

Zones are published per ZIP code, not per county, so this is the exact answer rather than the county's average. The station column is the nearest one to that ZIP code's centroid and how far away it is — the same figure the tools use, shown here so you can see which ZIP codes are well covered and which are reaching.

ZIP code	USDA zone	Nearest NOAA station	Distance
47933	5b	Crawfordsville 6 SE, IN	9.4 km
47940	6a	Crawfordsville 6 SE, IN	13.6 km
47954	6a	Crawfordsville 6 SE, IN	11.5 km
47955	6a	Lafayette 8 S, IN	11.8 km
47965	5b	Crawfordsville 6 SE, IN	11.5 km
47967	6a	Lafayette 8 S, IN	14.0 km
47968	6a	Crawfordsville 6 SE, IN	6.5 km
47989	5b	Rockville, IN	21.0 km
47990	5b	Crawfordsville 6 SE, IN	22.9 km
47994	6a	Attica 2E, IN	14.9 km

ZIP-code positions are area centroids, so a large rural ZIP code's listed distance is measured from the middle of its area rather than from any particular address in it.

When to start seeds in Montgomery County

Every date below is anchored on the last spring freeze at each station and reported as a range across all 4 of them, because no one station speaks for the county.

Crop	Job	When	Offset
🧅 Green Onions	Start indoors	February 23 – March 5	8 wk before
🌶️ Peppers	Start indoors	February 23 – March 5	8 wk before
🥦 Broccoli	Start indoors	March 9 – March 19	6 wk before
🥬 Cabbage	Start indoors	March 9 – March 19	6 wk before
🥬 Collards	Start indoors	March 9 – March 19	6 wk before
🥬 Kale	Start indoors	March 9 – March 19	6 wk before
🥬 Leaf Lettuce	Start indoors	March 9 – March 19	6 wk before
🫛 Peas	Direct sow	March 9 – March 19	6 wk before
🥬 Spinach	Direct sow	March 9 – March 19	6 wk before
🍠 Sweet Potato	Start indoors	March 9 – March 19	6 wk before
🍅 Tomatoes	Start indoors	March 9 – March 19	6 wk before
🥬 Bok Choy	Start indoors	March 16 – March 26	5 wk before
🥬 Kohlrabi	Start indoors	March 16 – March 26	5 wk before
🥬 Swiss Chard	Start indoors	March 16 – March 26	5 wk before
🥬 Arugula	Direct sow	March 23 – April 2	4 wk before
🥬 Baby Salad Greens	Direct sow	March 23 – April 2	4 wk before
🥕 Beets	Direct sow	March 23 – April 2	4 wk before
🧅 Green Onions	Direct sow	March 23 – April 2	4 wk before
🥬 Mustard Greens	Direct sow	March 23 – April 2	4 wk before
🌶️ Okra	Start indoors	March 23 – April 2	4 wk before
🌱 Radishes	Direct sow	March 23 – April 2	4 wk before
🥔 Turnips	Direct sow	March 23 – April 2	4 wk before
🥬 Cabbage	Set out	March 30 – April 9	3 wk before
🥕 Carrots	Direct sow	March 30 – April 9	3 wk before
🥬 Collards	Direct sow	March 30 – April 9	3 wk before
🥬 Collards	Set out	March 30 – April 9	3 wk before
🥒 Cucumbers	Start indoors	March 30 – April 9	3 wk before
🧅 Green Onions	Set out	March 30 – April 9	3 wk before
🥬 Kale	Direct sow	March 30 – April 9	3 wk before
🥬 Kale	Set out	March 30 – April 9	3 wk before
🥬 Kohlrabi	Direct sow	March 30 – April 9	3 wk before
🥬 Kohlrabi	Set out	March 30 – April 9	3 wk before
🥬 Leaf Lettuce	Direct sow	March 30 – April 9	3 wk before
🎃 Pumpkins	Start indoors	March 30 – April 9	3 wk before
🎃 Summer Squash	Start indoors	March 30 – April 9	3 wk before
🎃 Winter Squash	Start indoors	March 30 – April 9	3 wk before
🥒 Zucchini	Start indoors	March 30 – April 9	3 wk before
🥬 Bok Choy	Direct sow	April 6 – April 16	2 wk before
🥬 Bok Choy	Set out	April 6 – April 16	2 wk before
🥦 Broccoli	Set out	April 6 – April 16	2 wk before
🌿 Cilantro	Direct sow	April 6 – April 16	2 wk before
🥬 Leaf Lettuce	Set out	April 6 – April 16	2 wk before
🥬 Swiss Chard	Direct sow	April 6 – April 16	2 wk before
🥬 Swiss Chard	Set out	April 6 – April 16	2 wk before
🌿 Dill	Direct sow	April 13 – April 23	1 wk before
🫘 Bush Beans	Direct sow	April 27 – May 7	1 wk after
🥒 Cucumbers	Set out	April 27 – May 7	1 wk after
🎃 Pumpkins	Direct sow	April 27 – May 7	1 wk after
🎃 Pumpkins	Set out	April 27 – May 7	1 wk after
🎃 Summer Squash	Direct sow	April 27 – May 7	1 wk after
🎃 Summer Squash	Set out	April 27 – May 7	1 wk after
🌽 Sweet Corn	Direct sow	April 27 – May 7	1 wk after
🍅 Tomatoes	Set out	April 27 – May 7	1 wk after
🎃 Winter Squash	Direct sow	April 27 – May 7	1 wk after
🎃 Winter Squash	Set out	April 27 – May 7	1 wk after
🥒 Zucchini	Direct sow	April 27 – May 7	1 wk after
🥒 Zucchini	Set out	April 27 – May 7	1 wk after
🥒 Cucumbers	Direct sow	May 4 – May 14	2 wk after
🌶️ Okra	Direct sow	May 4 – May 14	2 wk after
🌶️ Okra	Set out	May 4 – May 14	2 wk after
🌶️ Peppers	Set out	May 4 – May 14	2 wk after
🫘 Southern Peas	Direct sow	May 4 – May 14	2 wk after
🍠 Sweet Potato	Set out	May 4 – May 14	2 wk after

Offsets are published guidance; the dates they land on are computed from measured NOAA normals. The seed-starting tool does this for your own ZIP code and counts the days.

What survives the winter changes across Montgomery County

Zone 6a carries 51 of 74 perennial edibles; zone 5b carries 48. The best number is not always the warmest zone — the count peaks in the middle and falls both ways, because the warm end loses plants to insufficient winter chill and summer heat, not to cold.

Hardiness ranges are a judgement, published by growers rather than measured; the zone they are compared against is measured. On a warm-end verdict, check with your local extension service — a coastal zone 8 and an inland zone 8 are not the same summer.

Cautious — shortens the seasonMedian across stationsOptimistic

Last spring freeze: Plan to May 15 to be careful. Median April 20 – April 30 across 4 stations; April 6 is the optimistic end.
First fall freeze: Plan to September 26 to be careful. Median October 12 – October 20 across 4 stations; November 2 is the optimistic end.

NOAA publishes these as probabilities, not averages — the middle figure is a median, so half of years fall either side of it. The cautious end is the 10% tail: in roughly nine years in ten the freeze falls on the safe side of it.

The 4 stations behind these numbers

All 4 NOAA stations whose normals this page quotes, spanning about 60 km north to south. Every one is named with its identifier in the station list below — this page does not single one out, because no one station speaks for a whole county.

A relative sketch, not a map with a projection: longitude is adjusted for latitude so the shape is not stretched, and there is no basemap. For the one station nearest a specific address, with its real distance, use the ZIP lookup above.

These are the stations this county's ZIP codes actually cite as nearest — not a claim that each one sits inside its boundary, since a rural ZIP legitimately reaches over it. Every figure above comes from them, and each is named so you can check it.

Station	NOAA ID	Last spring freeze	First fall freeze	Season
Attica 2E, IN	USC00120331	April 22	October 17	176 days
Crawfordsville 6 SE, IN	USC00121873	April 27	October 12	167 days
Lafayette 8 S, IN	USC00124715	April 20	October 20	182 days
Rockville, IN	USC00127522	April 30	October 12	164 days

These are medians, not averages — NOAA publishes freeze dates as a probability distribution, and half of years freeze later than the date shown.

Your own ZIP

Work out your own dates

This page describes a whole county. Every tool below answers for one ZIP code, which is the grain the underlying data is published at.

Other places to compare

Montgomery County sits in Indiana. That page carries the whole state's zone spread, its metro areas, and every other county in it with a page here.

More of Indiana

Counties with the same zones — 5b–6a

Matched on the exact zone set, not a dominant zone, so the winter answer on these pages really is the same one as here.

Gear

If you want to act on this

Each link opens an Amazon search rather than a product we picked. We have not tested these and do not rank them — the search is the honest version, and you choose.

Trunk wrapZone 5b is cold enough that winter sun on a young trunk does more damage than the cold does.
Row cover and frost clothThe season here closes at the first fall freeze dated above — a cover buys back some of those days at the end.
MulchFor the perennials nearest their cold limit in zone 5b, where an insulated crown is what decides whether they come back.

As an Amazon Associate we earn from qualifying purchases. That costs you nothing extra, and it buys no influence over anything on this site: the dates come from NOAA normals and the zones from the USDA, and no product affects either.

Sources

Where these numbers come from

Hardiness zones are the USDA 2023 Plant Hardiness Zone Map, published per ZIP code by PRISM at Oregon State. Freeze dates and growing-season lengths are NOAA 1991–2020 Climate Normals, taken per station and cited above by name and NOAA ID.

County boundaries come from the Census ZCTA-to-county relation, which is what places each ZIP code — and which treats parishes, boroughs and census areas as county equivalents. No station is chosen to represent this county: every range above is taken across all of them and the count is stated, because picking one would be a judgement dressed as a measurement.