Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 78593 — Santa Rosa, TX

ZIP code 78593 (Santa Rosa, Cameron County) is in USDA zone 10a: the coldest winter night averages 30 to 35 °F.

Where ZIP 78593 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone10a30 to 35 °F
Coldest night−1.1 to 1.7 °C
Last frostrare
First frostrare
2012 zone9b

Was 9b on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 10a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Santa Rosa, TX…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates

A 32 °F frost doesn't happen here in most winters. At the nearest station (NOAA station Santa Rosa 3 Wnw, TX — 3 miles away, elevation 49 ft) the median growing season is 355 days. When frost does come, it is a midwinter night or two; cover tender plants when a freeze is forecast.

Frost data: NOAA NCEI U.S. Climate Normals 1991–2020.

When spring arrived in 2026

In 2026, spring leaf-out near 78593 came on Jan 9 — 7 days earlier than the 1991–2020 average (Jan 16).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Soil in Santa Rosa, TX

The soil mapped at the center of ZIP 78593 is Raymondville — clay loam, moderately well drained.

TextureClay loamholds water and nutrients; slow to drain and warm up
pH8.2alkaline; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter2%moderate
Hydrologic groupCwater soaks in slowly
Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Raymondville clay loam.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 78593; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Santa Rosa, TX

Summer high97 °Faverage high, August
Winter low49 °Faverage low, January
Hot days166days a year at 90 °F or more
Freezing nights2nights a year at 32 °F or less
Growing degree days9,080base 50 °F — the season’s usable heat
Longest day13 h 47 mindaylight on June 21
Shortest day10 h 29 mindaylight on December 21
Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb
Precipitation24.6 inper year, rain and melted snow

Average high and low, by month

40°50°60°70°80°90°100°110°January: average high 71 °F, low 49 °F 71°49° JanFebruary: average high 76 °F, low 53 °F 76°53° FebMarch: average high 81 °F, low 58 °F 81°58° MarApril: average high 86 °F, low 64 °F 86°64° AprMay: average high 91 °F, low 71 °F 91°71° MayJune: average high 95 °F, low 75 °F 95°75° JunJuly: average high 96 °F, low 76 °F 96°76° JulAugust: average high 97 °F, low 75 °F 97°75° AugSeptember: average high 93 °F, low 72 °F 93°72° SepOctober: average high 88 °F, low 65 °F 88°65° OctNovember: average high 80 °F, low 57 °F 80°57° NovDecember: average high 73 °F, low 50 °F 73°50° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 1.12 in precipitation 1.1 JanFebruary: 1.00 in precipitation 1.0 FebMarch: 1.40 in precipitation 1.4 MarApril: 1.39 in precipitation 1.4 AprMay: 2.48 in precipitation 2.5 MayJune: 2.88 in precipitation 2.9 JunJuly: 1.67 in precipitation 1.7 JulAugust: 2.10 in precipitation 2.1 AugSeptember: 5.56 in precipitation 5.6 SepOctober: 2.66 in precipitation 2.7 OctNovember: 1.23 in precipitation 1.2 NovDecember: 1.12 in precipitation, 0.1 in snowfall 1.1 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Santa Rosa 3 Wnw, TX (3 mi away); precipitation: Santa Rosa 3 Wnw, TX (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 10a.

7856210a
La Villa, TX · 4 mi
7859410a
Sebastian, TX · 5 mi
7853510a
Combes, TX · 6 mi
7855110a
Harlingen, TX · 7 mi
7855210a
Harlingen, TX · 7 mi
7856910a
Lyford, TX · 9 mi
7855910a
La Feria, TX · 9 mi
7857010a
Mercedes, TX · 9 mi

Texas planting zones →

Questions about 78593

What planting zone is ZIP code 78593?

ZIP code 78593 (Santa Rosa, TX) is in USDA hardiness zone 10a on the 2023 map: the coldest night of an average winter reaches 30 to 35 °F (−1.1 to 1.7 °C).

How much rain and snow does 78593 get?

About 24.6 inches of precipitation a year (NOAA 1991–2020 normals, Santa Rosa 3 Wnw station).

How hot do summers get in Santa Rosa, TX?

The average high peaks at 97 °F in August, with about 166 days a year at 90 °F or more.

What kind of soil does 78593 have?

The USDA soil survey maps Raymondville at the center of ZIP 78593: clay loam, moderately well drained, pH about 8.2 (alkaline).

Did spring come early in Santa Rosa, TX in 2026?

Spring leaf-out near 78593 came on Jan 9 in 2026, 7 days earlier than the 1991–2020 average (Jan 16), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Santa Rosa, TX?

Short-day onions: the longest day near 78593 is 13 h 47 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.

Did the zone for 78593 change?

Yes. The 2012 USDA map put 78593 in zone 9b; the 2023 map puts it in zone 10a. The newer map uses 1991–2020 data and more weather stations.