What USDA hardiness zone is Colorado County, Texas?

Every ZIP code in Colorado County, Texas is USDA hardiness zone 9a, from the USDA 2023 Plant Hardiness Zone Map.

When is the last spring frost in Colorado County, Texas?

The median last spring freeze runs February 17 – March 9 across the 4 NOAA weather stations serving Colorado County, Texas, from NOAA 1991-2020 Climate Normals. Half of years freeze later than the median.

Texas

Planting zones in Colorado County, Texas

Every ZIP code in this county is USDA zone 9a — 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 9a The same in all 12 ZIP codes

ZIP codes 12 12 have a NOAA station within range

Weather stations 4 NOAA 1991–2020 normals, across 960 sq mi

Your ZIP code

Get the exact answer for your address

Everything above describes Colorado County, Texas 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 Colorado County is closing

Nothing in the 32-crop table still has time to mature here. The first fall freeze normally arrives November 20 – December 5 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 January 12 – December 29 — counted back from a last spring freeze of February 17 – March 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 March 9 – November 20 as growing season (256 days). Widening to any single station gives February 17 – December 5 (291 days).

That is a 35-day difference inside one county — which is why this page gives ranges rather than a single planting date. The ZIP lookup above resolves it to one station.

Your freeze dates

Last spring freeze February 17 – March 9

First fall freeze November 20 – December 5

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 255–297 days depending which station you are nearest, as published by NOAA rather than computed from the dates above. Summer highs average 93.9–95.7 °F in June–August. That is past the point where tomato and pepper pollen fails and cool-season greens bolt, so in this county heat decides as much as frost does. Summer rain over the same months runs 10.2–13.2" 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 99% 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 96 °F summer afternoon drying the soil faster than a cool one.

Every ZIP code in Colorado 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
77412	9a	Eagle Lake Resch Ctr, TX	11.2 km
77434	9a	Eagle Lake Resch Ctr, TX	11.8 km
77442	9a	Eagle Lake Resch Ctr, TX	23.9 km
77460	9a	El Campo, TX	24.8 km
77470	9a	Columbus, TX	18.8 km
77475	9a	Columbus, TX	23.0 km
78933	9a	Eagle Lake Resch Ctr, TX	20.1 km
78934	9a	Columbus, TX	0.7 km
78935	9a	Eagle Lake Resch Ctr, TX	10.0 km
78943	9a	Columbus, TX	2.2 km
78951	9a	Hallettsville 2 N, TX	19.4 km
78962	9a	Columbus, TX	15.8 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 Colorado 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
🥦 Broccoli	Start indoors	January 6 – January 26	6 wk before
🥬 Cabbage	Start indoors	January 6 – January 26	6 wk before
🥬 Collards	Start indoors	January 6 – January 26	6 wk before
🥬 Kale	Start indoors	January 6 – January 26	6 wk before
🥬 Leaf Lettuce	Start indoors	January 6 – January 26	6 wk before
🫛 Peas	Direct sow	January 6 – January 26	6 wk before
🥬 Spinach	Direct sow	January 6 – January 26	6 wk before
🍠 Sweet Potato	Start indoors	January 6 – January 26	6 wk before
🍅 Tomatoes	Start indoors	January 6 – January 26	6 wk before
🧅 Green Onions	Start indoors	January 12 – December 29	8 wk before
🌶️ Peppers	Start indoors	January 12 – December 29	8 wk before
🥬 Bok Choy	Start indoors	January 13 – February 2	5 wk before
🥬 Kohlrabi	Start indoors	January 13 – February 2	5 wk before
🥬 Swiss Chard	Start indoors	January 13 – February 2	5 wk before
🥬 Arugula	Direct sow	January 20 – February 9	4 wk before
🥬 Baby Salad Greens	Direct sow	January 20 – February 9	4 wk before
🥕 Beets	Direct sow	January 20 – February 9	4 wk before
🧅 Green Onions	Direct sow	January 20 – February 9	4 wk before
🥬 Mustard Greens	Direct sow	January 20 – February 9	4 wk before
🌶️ Okra	Start indoors	January 20 – February 9	4 wk before
🌱 Radishes	Direct sow	January 20 – February 9	4 wk before
🥔 Turnips	Direct sow	January 20 – February 9	4 wk before
🥬 Cabbage	Set out	January 27 – February 16	3 wk before
🥕 Carrots	Direct sow	January 27 – February 16	3 wk before
🥬 Collards	Direct sow	January 27 – February 16	3 wk before
🥬 Collards	Set out	January 27 – February 16	3 wk before
🥒 Cucumbers	Start indoors	January 27 – February 16	3 wk before
🧅 Green Onions	Set out	January 27 – February 16	3 wk before
🥬 Kale	Direct sow	January 27 – February 16	3 wk before
🥬 Kale	Set out	January 27 – February 16	3 wk before
🥬 Kohlrabi	Direct sow	January 27 – February 16	3 wk before
🥬 Kohlrabi	Set out	January 27 – February 16	3 wk before
🥬 Leaf Lettuce	Direct sow	January 27 – February 16	3 wk before
🎃 Pumpkins	Start indoors	January 27 – February 16	3 wk before
🎃 Summer Squash	Start indoors	January 27 – February 16	3 wk before
🎃 Winter Squash	Start indoors	January 27 – February 16	3 wk before
🥒 Zucchini	Start indoors	January 27 – February 16	3 wk before
🥬 Bok Choy	Direct sow	February 3 – February 23	2 wk before
🥬 Bok Choy	Set out	February 3 – February 23	2 wk before
🥦 Broccoli	Set out	February 3 – February 23	2 wk before
🌿 Cilantro	Direct sow	February 3 – February 23	2 wk before
🥬 Leaf Lettuce	Set out	February 3 – February 23	2 wk before
🥬 Swiss Chard	Direct sow	February 3 – February 23	2 wk before
🥬 Swiss Chard	Set out	February 3 – February 23	2 wk before
🌿 Dill	Direct sow	February 10 – March 2	1 wk before
🫘 Bush Beans	Direct sow	February 24 – March 16	1 wk after
🥒 Cucumbers	Set out	February 24 – March 16	1 wk after
🎃 Pumpkins	Direct sow	February 24 – March 16	1 wk after
🎃 Pumpkins	Set out	February 24 – March 16	1 wk after
🎃 Summer Squash	Direct sow	February 24 – March 16	1 wk after
🎃 Summer Squash	Set out	February 24 – March 16	1 wk after
🌽 Sweet Corn	Direct sow	February 24 – March 16	1 wk after
🍅 Tomatoes	Set out	February 24 – March 16	1 wk after
🎃 Winter Squash	Direct sow	February 24 – March 16	1 wk after
🎃 Winter Squash	Set out	February 24 – March 16	1 wk after
🥒 Zucchini	Direct sow	February 24 – March 16	1 wk after
🥒 Zucchini	Set out	February 24 – March 16	1 wk after
🥒 Cucumbers	Direct sow	March 3 – March 23	2 wk after
🌶️ Okra	Direct sow	March 3 – March 23	2 wk after
🌶️ Okra	Set out	March 3 – March 23	2 wk after
🌶️ Peppers	Set out	March 3 – March 23	2 wk after
🫘 Southern Peas	Direct sow	March 3 – March 23	2 wk after
🍠 Sweet Potato	Set out	March 3 – March 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 9a winter

Of 74 perennial edibles, 46 come through a zone 9a winter — and 25 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: Elderberry, Horseradish, Sunchoke, Walking Onion, Chives, Mint, American Persimmon, European Plum.

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.

At least one station here freezes across the new year, which puts the two ends of a spread on opposite sides of the calendar. Drawing it would produce a bar spanning almost the whole year and meaning nothing, so none is drawn.

The 4 stations behind these numbers

All 4 NOAA stations whose normals this page quotes, spanning about 55 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
Columbus, TX	USC00411911	March 9	November 20	255 days
Eagle Lake Resch Ctr, TX	USC00412676	February 21	December 1	285 days
El Campo, TX	USC00412786	February 23	December 5	287 days
Hallettsville 2 N, TX	USC00413873	February 17	December 4	297 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

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

More of Texas

Counties with the same zones — 9a

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.

Shade clothSummer highs here average 96 °F, at or above the 90 °F point where lettuce and spinach bolt and tomato pollen fails.
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.

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.