What USDA hardiness zone is Tuscola County, Michigan?

Every ZIP code in Tuscola County, Michigan is USDA hardiness zone 6a, from the USDA 2023 Plant Hardiness Zone Map.

When is the last spring frost in Tuscola County, Michigan?

The median last spring freeze runs May 4 – May 9 across the 4 NOAA weather stations serving Tuscola County, Michigan, from NOAA 1991-2020 Climate Normals. Half of years freeze later than the median.

Michigan

Planting zones in Tuscola County, Michigan

Every ZIP code in this county is USDA zone 6a — so unlike most of the places people look up, there is one right answer here and it holds wherever you are in the county.

USDA zone 6a The same in all 13 ZIP codes

ZIP codes 13 13 have a NOAA station within range

Weather stations 4 NOAA 1991–2020 normals, across 805 sq mi

Your ZIP code

Get the exact answer for your address

Everything above describes Tuscola County, Michigan 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 Tuscola County is closing

Nothing in the 32-crop table still has time to mature here. The first fall freeze normally arrives October 7 – October 13 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 March 9 – March 14 — counted back from a last spring freeze of May 4 – May 9 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 May 9 – October 7 as growing season (151 days). Widening to any single station gives May 4 – October 13 (162 days).

Your freeze dates

Last spring freeze May 4 – May 9

First fall freeze October 7 – October 13

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 150–161 days depending which station you are nearest, as published by NOAA rather than computed from the dates above. Summer highs average 78.7–80.1 °F in June–August. Summer rain over the same months runs 9.6–11.2" 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. The middle station covers about 85% of it, so expect to make up the rest. The inches are NOAA's published normals; the inch a week is a rule of thumb, and it takes no account of a 80 °F summer afternoon drying the soil faster than a cool one.

Every ZIP code in Tuscola 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
48435	6a	Lapeer 2W, MI	20.8 km
48701	6a	Caro WWTP, MI	17.6 km
48723	6a	Caro WWTP, MI	0.7 km
48726	6a	Cass City 1 Ssw, MI	2.6 km
48729	6a	Cass City 1 Ssw, MI	10.0 km
48733	6a	Caro WWTP, MI	17.2 km
48735	6a	Cass City 1 Ssw, MI	11.6 km
48741	6a	Caro WWTP, MI	19.4 km
48744	6a	Caro WWTP, MI	15.3 km
48746	6a	Vassar, MI	12.2 km
48757	6a	Vassar, MI	13.8 km
48767	6a	Caro WWTP, MI	19.4 km
48768	6a	Vassar, MI	0.7 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 Tuscola 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	March 9 – March 14	8 wk before
🌶️ Peppers	Start indoors	March 9 – March 14	8 wk before
🥦 Broccoli	Start indoors	March 23 – March 28	6 wk before
🥬 Cabbage	Start indoors	March 23 – March 28	6 wk before
🥬 Collards	Start indoors	March 23 – March 28	6 wk before
🥬 Kale	Start indoors	March 23 – March 28	6 wk before
🥬 Leaf Lettuce	Start indoors	March 23 – March 28	6 wk before
🫛 Peas	Direct sow	March 23 – March 28	6 wk before
🥬 Spinach	Direct sow	March 23 – March 28	6 wk before
🍠 Sweet Potato	Start indoors	March 23 – March 28	6 wk before
🍅 Tomatoes	Start indoors	March 23 – March 28	6 wk before
🥬 Bok Choy	Start indoors	March 30 – April 4	5 wk before
🥬 Kohlrabi	Start indoors	March 30 – April 4	5 wk before
🥬 Swiss Chard	Start indoors	March 30 – April 4	5 wk before
🥬 Arugula	Direct sow	April 6 – April 11	4 wk before
🥬 Baby Salad Greens	Direct sow	April 6 – April 11	4 wk before
🥕 Beets	Direct sow	April 6 – April 11	4 wk before
🧅 Green Onions	Direct sow	April 6 – April 11	4 wk before
🥬 Mustard Greens	Direct sow	April 6 – April 11	4 wk before
🌶️ Okra	Start indoors	April 6 – April 11	4 wk before
🌱 Radishes	Direct sow	April 6 – April 11	4 wk before
🥔 Turnips	Direct sow	April 6 – April 11	4 wk before
🥬 Cabbage	Set out	April 13 – April 18	3 wk before
🥕 Carrots	Direct sow	April 13 – April 18	3 wk before
🥬 Collards	Direct sow	April 13 – April 18	3 wk before
🥬 Collards	Set out	April 13 – April 18	3 wk before
🥒 Cucumbers	Start indoors	April 13 – April 18	3 wk before
🧅 Green Onions	Set out	April 13 – April 18	3 wk before
🥬 Kale	Direct sow	April 13 – April 18	3 wk before
🥬 Kale	Set out	April 13 – April 18	3 wk before
🥬 Kohlrabi	Direct sow	April 13 – April 18	3 wk before
🥬 Kohlrabi	Set out	April 13 – April 18	3 wk before
🥬 Leaf Lettuce	Direct sow	April 13 – April 18	3 wk before
🎃 Pumpkins	Start indoors	April 13 – April 18	3 wk before
🎃 Summer Squash	Start indoors	April 13 – April 18	3 wk before
🎃 Winter Squash	Start indoors	April 13 – April 18	3 wk before
🥒 Zucchini	Start indoors	April 13 – April 18	3 wk before
🥬 Bok Choy	Direct sow	April 20 – April 25	2 wk before
🥬 Bok Choy	Set out	April 20 – April 25	2 wk before
🥦 Broccoli	Set out	April 20 – April 25	2 wk before
🌿 Cilantro	Direct sow	April 20 – April 25	2 wk before
🥬 Leaf Lettuce	Set out	April 20 – April 25	2 wk before
🥬 Swiss Chard	Direct sow	April 20 – April 25	2 wk before
🥬 Swiss Chard	Set out	April 20 – April 25	2 wk before
🌿 Dill	Direct sow	April 27 – May 2	1 wk before
🫘 Bush Beans	Direct sow	May 11 – May 16	1 wk after
🥒 Cucumbers	Set out	May 11 – May 16	1 wk after
🎃 Pumpkins	Direct sow	May 11 – May 16	1 wk after
🎃 Pumpkins	Set out	May 11 – May 16	1 wk after
🎃 Summer Squash	Direct sow	May 11 – May 16	1 wk after
🎃 Summer Squash	Set out	May 11 – May 16	1 wk after
🌽 Sweet Corn	Direct sow	May 11 – May 16	1 wk after
🍅 Tomatoes	Set out	May 11 – May 16	1 wk after
🎃 Winter Squash	Direct sow	May 11 – May 16	1 wk after
🎃 Winter Squash	Set out	May 11 – May 16	1 wk after
🥒 Zucchini	Direct sow	May 11 – May 16	1 wk after
🥒 Zucchini	Set out	May 11 – May 16	1 wk after
🥒 Cucumbers	Direct sow	May 18 – May 23	2 wk after
🌶️ Okra	Direct sow	May 18 – May 23	2 wk after
🌶️ Okra	Set out	May 18 – May 23	2 wk after
🌶️ Peppers	Set out	May 18 – May 23	2 wk after
🫘 Southern Peas	Direct sow	May 18 – May 23	2 wk after
🍠 Sweet Potato	Set out	May 18 – May 23	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 lives through a zone 6a winter

Of 74 perennial edibles, 51 come through a zone 6a winter — and 0 fail here for being too warm rather than too cold, needing more winter chill than this county gets or more heat than they tolerate. Among the ones that work: Cranberry, Honeyberry, Lingonberry, Apple, Aronia, Black Currant, Elderberry, Gooseberry.

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 24 to be careful. Median May 4 – May 9 across 4 stations; April 21 is the optimistic end.
First fall freeze: Plan to September 24 to be careful. Median October 7 – October 13 across 4 stations; October 29 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 59 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
Caro WWTP, MI	USC00201299	May 7	October 9	154 days
Cass City 1 Ssw, MI	USC00201361	May 7	October 10	152 days
Lapeer 2W, MI	USC00204659	May 4	October 13	161 days
Vassar, MI	USC00208443	May 9	October 7	150 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

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

More of Michigan

Counties with the same zones — 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 6a 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 6a, 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.