What USDA hardiness zone is Austin-Round Rock-San Marcos, TX?

Austin-Round Rock-San Marcos, TX spans USDA hardiness zones 8b to 9a. 88% of its ZIP codes are zone 9a, so there is no single zone for the metro.

When is the last spring frost in Austin-Round Rock-San Marcos, TX?

The median last spring freeze runs February 20 – March 17 across the 15 NOAA weather stations serving Austin-Round Rock-San Marcos, TX, from NOAA 1991-2020 Climate Normals. Half of years freeze later than the median.

Place guide

Planting zones in Austin-Round Rock-San Marcos, TX

This metro spans USDA zones 8b to 9a, so there is no single zone for Austin-Round Rock-San Marcos, TX and anyone who gives you one is rounding. 88% of its ZIP codes are zone 9a; the rest are not.

USDA zones 8b–9a 2 zones across 89 ZIP codes

ZIP codes 89 89 have a NOAA station within range

Weather stations 15 NOAA 1991–2020 normals, across 4,220 sq mi

Your ZIP code

Get the exact answer for your address

Everything above describes Austin-Round Rock-San Marcos, TX 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 Austin-Round Rock-San Marcos, TX is closing

Nothing in the 32-crop table still has time to mature here. The first fall freeze normally arrives November 13 – December 3 across the 15 NOAA stations serving this metro area .

Your next season already has a date

The first job of it is 🧅 Green Onions, start indoors, around January 3 – December 26 — counted back from a last spring freeze of February 20 – March 17 here.

Every spring date for your ZIP →

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

All 15 stations agreeAt least one station

Every one of the 15 NOAA stations serving this metro area counts March 17 – November 13 as growing season (241 days). Widening to any single station gives February 20 – December 3 (286 days).

That is a 45-day difference inside one metro area — which is why this page gives ranges rather than a single planting date. The ZIP lookup above resolves it to one station.

Which zone you are in depends where you are

Austin-Round Rock-San Marcos, TX covers 2 hardiness zones. A guide that gives the metro one zone has picked whichever is largest and rounded everyone else into it — which is fine for the 88% in zone 9a and wrong for the other 12%. Here is the actual split.

Zone	ZIP codes	Share
9a	78	88%
8b	11	12%

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

Your freeze dates

Last spring freeze February 20 – March 17

First fall freeze November 13 – December 3

Those are the earliest and latest medians among the 15 stations serving this metro — not an average, and not one station standing in for the rest. Half of years freeze later than a station's own median.

The spread is the point. Even in a metro that is one hardiness zone throughout, its stations disagree about the last spring freeze. Hardiness zone and frost date measure different things — a zone is the average annual coldest night, a freeze date is when the season turns — and a place can be uniform in one and varied in the other. Use the tools below with your own ZIP rather than the ends of this range.

Your growing season

NOAA publishes a growing-season length for each station, and across the 15 stations serving Austin-Round Rock-San Marcos, TX it runs 242–291 days . That figure is published, not computed from the two freeze dates — subtracting one from the other gives the wrong answer wherever a season crosses New Year. Mean summer high (June–August) runs 93–96 °F , at or above the 90 °F point where cool-season crops bolt and tomato and pepper pollen fails — so midsummer sowings of lettuce and its relatives are worth holding here. Summer rain over the same months runs 7.3–9.5" across those 14 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 61% 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 95 °F summer afternoon drying the soil faster than a cool one.

When to start seeds in Austin-Round Rock-San Marcos, TX

Every spring job for 63 crop dates, counted from this metro's own last spring freeze. Each is a range across all 15 stations — the earliest and latest that job falls anywhere in the metro — because no one station speaks for the whole area.

Crop	Job	When	Offset
Green Onions	Start indoors	January 3 – December 26	8 weeks before
Peppers	Start indoors	January 3 – December 26	8 weeks before
Broccoli	Start indoors	January 9 – February 3	6 weeks before
Cabbage	Start indoors	January 9 – February 3	6 weeks before
Collards	Start indoors	January 9 – February 3	6 weeks before
Kale	Start indoors	January 9 – February 3	6 weeks before
Leaf Lettuce	Start indoors	January 9 – February 3	6 weeks before
Peas	Direct sow	January 9 – February 3	6 weeks before
Spinach	Direct sow	January 9 – February 3	6 weeks before
Sweet Potato	Start indoors	January 9 – February 3	6 weeks before
Tomatoes	Start indoors	January 9 – February 3	6 weeks before
Bok Choy	Start indoors	January 16 – February 10	5 weeks before
Kohlrabi	Start indoors	January 16 – February 10	5 weeks before
Swiss Chard	Start indoors	January 16 – February 10	5 weeks before
Arugula	Direct sow	January 23 – February 17	4 weeks before
Baby Salad Greens	Direct sow	January 23 – February 17	4 weeks before
Beets	Direct sow	January 23 – February 17	4 weeks before
Green Onions	Direct sow	January 23 – February 17	4 weeks before
Mustard Greens	Direct sow	January 23 – February 17	4 weeks before
Okra	Start indoors	January 23 – February 17	4 weeks before
Radishes	Direct sow	January 23 – February 17	4 weeks before
Turnips	Direct sow	January 23 – February 17	4 weeks before
Cabbage	Set out	January 30 – February 24	3 weeks before
Carrots	Direct sow	January 30 – February 24	3 weeks before
Collards	Direct sow	January 30 – February 24	3 weeks before
Collards	Set out	January 30 – February 24	3 weeks before
Cucumbers	Start indoors	January 30 – February 24	3 weeks before
Green Onions	Set out	January 30 – February 24	3 weeks before
Kale	Direct sow	January 30 – February 24	3 weeks before
Kale	Set out	January 30 – February 24	3 weeks before
Kohlrabi	Direct sow	January 30 – February 24	3 weeks before
Kohlrabi	Set out	January 30 – February 24	3 weeks before
Leaf Lettuce	Direct sow	January 30 – February 24	3 weeks before
Pumpkins	Start indoors	January 30 – February 24	3 weeks before
Summer Squash	Start indoors	January 30 – February 24	3 weeks before
Winter Squash	Start indoors	January 30 – February 24	3 weeks before
Zucchini	Start indoors	January 30 – February 24	3 weeks before
Bok Choy	Direct sow	February 6 – March 3	2 weeks before
Bok Choy	Set out	February 6 – March 3	2 weeks before
Broccoli	Set out	February 6 – March 3	2 weeks before
Cilantro	Direct sow	February 6 – March 3	2 weeks before
Leaf Lettuce	Set out	February 6 – March 3	2 weeks before
Swiss Chard	Direct sow	February 6 – March 3	2 weeks before
Swiss Chard	Set out	February 6 – March 3	2 weeks before
Dill	Direct sow	February 13 – March 10	1 week before
Bush Beans	Direct sow	February 27 – March 24	1 week after
Cucumbers	Set out	February 27 – March 24	1 week after
Pumpkins	Direct sow	February 27 – March 24	1 week after
Pumpkins	Set out	February 27 – March 24	1 week after
Summer Squash	Direct sow	February 27 – March 24	1 week after
Summer Squash	Set out	February 27 – March 24	1 week after
Sweet Corn	Direct sow	February 27 – March 24	1 week after
Tomatoes	Set out	February 27 – March 24	1 week after
Winter Squash	Direct sow	February 27 – March 24	1 week after
Winter Squash	Set out	February 27 – March 24	1 week after
Zucchini	Direct sow	February 27 – March 24	1 week after
Zucchini	Set out	February 27 – March 24	1 week after
Cucumbers	Direct sow	March 6 – March 31	2 weeks after
Okra	Direct sow	March 6 – March 31	2 weeks after
Okra	Set out	March 6 – March 31	2 weeks after
Peppers	Set out	March 6 – March 31	2 weeks after
Southern Peas	Direct sow	March 6 – March 31	2 weeks after
Sweet Potato	Set out	March 6 – March 31	2 weeks after

The week offsets are conventional extension guidance and vary by variety; the freeze dates they are counted from are measured. For a single date rather than a range, run when do I start my seeds? with your own ZIP code.

What survives the winter changes across Austin-Round Rock-San Marcos, TX

Of 74 perennial fruits, nuts, berries, vegetables and herbs, 54 come through the winter in zone 8b and only 46 in zone 9a. That is a different garden at each end of the same metro.

Zone	ZIPs	Survive	Fail for being too warm
8b	11	54 of 74	11
9a	78	46 of 74	25

The last column is the counterintuitive one, and it is why the totals do not simply rise as the winters get milder. Most temperate fruit needs a documented number of hours below about 45 °F to break dormancy and set a crop, so an apple fails in a winter that is too warm; currants and rhubarb cook in the summer heat that comes with it. See the full list with reasons.

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 15 stations behind these numbers

All 15 NOAA stations whose normals this page quotes, spanning about 116 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 metro area.

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.

Every figure above comes from these, and each is named so you can check it. Which station serves a given ZIP code, and how far away it is, varies across the metro — the table below gives it per ZIP code rather than this page averaging it.

Station	NOAA ID	Last spring freeze	First fall freeze	Season
Austin 33 NW, TX	USW00023907	March 2	November 29	274 days
Austin 6S, TX	USC00410431	March 10	November 17	252 days
Austin Bergstrom AP, TX	USW00013904	March 12	November 16	252 days
Austin Great Hills, TX	USC00410433	March 11	November 20	254 days
Austin-Camp Mabry, TX	USW00013958	February 20	December 3	291 days
Canyon Dam, TX	USC00411429	March 1	December 1	276 days
Cedar Creek 5 S, TX	USC00411541	March 14	November 19	250 days
Dripping Springs 6 E, TX	USC00412585	March 17	November 13	242 days
Elgin 1 N, TX	USC00412820	March 4	November 24	264 days
Georgetown Lake, TX	USC00413507	March 6	November 24	259 days
Granger Dam, TX	USC00413686	March 5	November 22	261 days
Luling, TX	USC00415429	March 5	November 23	263 days
San Marcos, TX	USC00417983	February 28	November 29	273 days
Smithville, TX	USC00418415	March 12	November 19	251 days
Taylor 1Nw, TX	USC00418862	March 8	November 21	257 days

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

Every ZIP code in Austin-Round Rock-San Marcos, TX

Zones are published per ZIP code, not per metro area, so this is the exact answer rather than the metro area'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
76527	8b	Georgetown Lake, TX	19.1 km
76530	9a	Granger Dam, TX	9.9 km
76537	8b	Georgetown Lake, TX	19.3 km
76573	8b	Granger Dam, TX	20.6 km
76574	9a	Taylor 1Nw, TX	2.6 km
76578	9a	Taylor 1Nw, TX	17.9 km
78602	9a	Cedar Creek 5 S, TX	19.3 km
78610	9a	Austin 6S, TX	19.2 km
78612	9a	Cedar Creek 5 S, TX	8.8 km
78613	9a	Austin Great Hills, TX	11.5 km
78615	9a	Elgin 1 N, TX	11.2 km
78616	9a	Cedar Creek 5 S, TX	12.3 km
78617	9a	Austin Bergstrom AP, TX	8.3 km
78619	8b	Dripping Springs 6 E, TX	12.6 km
78620	8b	Dripping Springs 6 E, TX	14.3 km
78621	9a	Elgin 1 N, TX	3.2 km
78622	9a	Luling, TX	16.7 km
78626	9a	Georgetown Lake, TX	10.1 km
78628	9a	Georgetown Lake, TX	5.7 km
78633	8b	Georgetown Lake, TX	7.3 km
78634	9a	Taylor 1Nw, TX	12.6 km
78640	9a	San Marcos, TX	17.5 km
78641	9a	Austin 33 NW, TX	17.9 km
78642	8b	Austin 33 NW, TX	16.1 km
78644	9a	Luling, TX	22.0 km
78645	9a	Austin Great Hills, TX	20.1 km
78648	9a	Luling, TX	2.8 km
78650	9a	Elgin 1 N, TX	16.0 km
78652	9a	Dripping Springs 6 E, TX	15.4 km
78653	9a	Elgin 1 N, TX	14.7 km
78655	9a	San Marcos, TX	13.3 km
78656	9a	San Marcos, TX	13.9 km
78659	9a	Smithville, TX	22.4 km
78660	9a	Austin Great Hills, TX	16.7 km
78661	9a	Luling, TX	11.0 km
78662	9a	Cedar Creek 5 S, TX	8.6 km
78664	9a	Austin Great Hills, TX	15.3 km
78665	9a	Georgetown Lake, TX	16.3 km
78666	9a	San Marcos, TX	3.4 km
78669	8b	Austin 33 NW, TX	20.3 km
78674	9a	Georgetown Lake, TX	11.7 km
78676	8b	Canyon Dam, TX	20.1 km
78681	9a	Austin Great Hills, TX	14.9 km
78701	9a	Austin 6S, TX	5.2 km
78702	9a	Austin 6S, TX	4.6 km
78703	9a	Austin-Camp Mabry, TX	3.1 km
78704	9a	Austin 6S, TX	3.7 km
78705	9a	Austin-Camp Mabry, TX	3.6 km
78712	9a	Austin-Camp Mabry, TX	4.9 km
78717	9a	Austin Great Hills, TX	8.4 km
78719	9a	Austin Bergstrom AP, TX	4.9 km
78721	9a	Austin 6S, TX	7.0 km
78722	9a	Austin-Camp Mabry, TX	5.6 km
78723	9a	Austin-Camp Mabry, TX	7.4 km
78724	9a	Austin 6S, TX	13.4 km
78725	8b	Austin Bergstrom AP, TX	8.6 km
78726	9a	Austin Great Hills, TX	7.3 km
78727	9a	Austin Great Hills, TX	4.9 km
78728	9a	Austin Great Hills, TX	8.8 km
78729	9a	Austin Great Hills, TX	4.9 km
78730	9a	Austin-Camp Mabry, TX	9.0 km
78731	9a	Austin-Camp Mabry, TX	3.1 km
78732	9a	Austin Great Hills, TX	12.6 km
78733	9a	Austin-Camp Mabry, TX	11.9 km
78734	9a	Austin Great Hills, TX	17.8 km
78735	9a	Austin-Camp Mabry, TX	11.9 km
78736	9a	Dripping Springs 6 E, TX	4.9 km
78737	8b	Dripping Springs 6 E, TX	5.6 km
78738	9a	Dripping Springs 6 E, TX	9.7 km
78739	9a	Dripping Springs 6 E, TX	10.5 km
78741	9a	Austin 6S, TX	1.9 km
78742	9a	Austin Bergstrom AP, TX	6.9 km
78744	9a	Austin Bergstrom AP, TX	4.4 km
78745	9a	Austin 6S, TX	6.6 km
78746	9a	Austin-Camp Mabry, TX	5.4 km
78747	9a	Austin Bergstrom AP, TX	8.8 km
78748	9a	Austin 6S, TX	11.3 km
78749	9a	Austin 6S, TX	11.9 km
78750	9a	Austin Great Hills, TX	3.5 km
78751	9a	Austin-Camp Mabry, TX	3.8 km
78752	9a	Austin-Camp Mabry, TX	5.6 km
78753	9a	Austin Great Hills, TX	9.6 km
78754	9a	Austin-Camp Mabry, TX	12.3 km
78756	9a	Austin-Camp Mabry, TX	1.9 km
78757	9a	Austin-Camp Mabry, TX	4.3 km
78758	9a	Austin Great Hills, TX	6.5 km
78759	9a	Austin Great Hills, TX	1.4 km
78953	9a	Cedar Creek 5 S, TX	22.4 km
78957	9a	Smithville, TX	1.8 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.

Your own ZIP

Work out your own dates

Each of these takes a ZIP code and answers for that ZIP alone, citing the station it used and how far away it is. There is a ZIP box in the header of every page.

What survives my winter?
Runs on the hardiness zone, so it answers for all of Austin-Round Rock-San Marcos, TX at once — zone across 74 perennial fruits, berries, vegetables and herbs.
When do I start my seeds?
Dates every spring job from your own last freeze — sow indoors, set out, direct sow.
When do I sow the next round?
How often each crop is worth re-sowing, and when the next sowing is due.
What can I still plant?
Counts the growing days left before your first fall freeze, crop by crop.

Other places to compare

These metros span exactly the same zones — 8b–9a — so the same plants are in and out of range across them. The freeze dates and the spring calendar are their own.

Gardening in Texas — zones 6b– 10b covers the whole state: how its 1,979 ZIP codes divide between 9 hardiness zones, and the freeze dates across every NOAA station in it.

Other metro areas in TX:

Lubbock, TX Zones 7b–8a
Corpus Christi, TX Zones 9b–10a
Longview, TX Zone 8b
Waco, TX Zones 8b–9a
El Paso, TX Zones 8a–8b
Beaumont-Port Arthur, TX Zones 9a–9b
Killeen-Temple, TX Zones 8b–9a
McAllen-Edinburg-Mission, TX Zones 9b–10a
Amarillo, TX Zone 7a
Abilene, TX Zone 8a
College Station-Bryan, TX Zones 8b–9a
Wichita Falls, TX Zone 8a

All 388 metro areas, by state

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 95 °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

The hardiness zone is the USDA 2023 Plant Hardiness Zone Map, published per ZIP code by PRISM at Oregon State. The freeze dates are NOAA's 1991–2020 Climate Normals, read from every station whose normals cover a ZIP code in this metro. Nothing here is estimated, and no station stands in for another.

This page names no single station on purpose. Picking one to represent a metro sounds reasonable and is not: the station serving the most ZIP codes is an artifact of where ZIP centroids happen to fall, and it selects a lock on the Monongahela for Pittsburgh and a far southern suburb for Chicago. A range across every station is true; a single cited date for a whole metro is not.

All metro areas