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

Planting zone for 96084 — Round Mountain, CA

ZIP code 96084 (Round Mountain, Shasta County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is June 3 and the first fall frost September 14.

Where ZIP 96084 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.

Zone9a20 to 25 °F
Coldest night−6.7 to −3.9 °C
Last frostJun 3
First frostSep 14
2012 zone9a

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 9a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Round Mountain, CA…

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 in Round Mountain, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostJune 3median — 50% chance of a later frost
Safe for tender plantsJune 19only 10% chance of frost after
First fall frostSeptember 14median — 10% chance by Sep 1
Growing season102 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 13 and returns around October 1.

From the NOAA station Burney, CA — 12 miles away, elevation 3,199 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 96084

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 22 – May 6
SpinachSow outdoors · Apr 22 – May 13
Broccoli, cabbageStart indoors · Mar 25 – Apr 8
Broccoli, cabbageTransplant · May 13 – May 27
Onion setsPlant outdoors · May 6 – May 20
PotatoesPlant outdoors · May 13 – May 27
LettuceSow outdoors · May 6 – May 20
Carrots, beetsSow outdoors · May 13 – May 27
TomatoesStart indoors · Apr 8 – Apr 22
TomatoesTransplant · Jun 10 – Jun 24
Peppers, eggplantStart indoors · Mar 25 – Apr 8
Peppers, eggplantTransplant · Jun 17 – Jul 1
BeansSow outdoors · Jun 10 – Jun 24
Sweet cornSow outdoors · Jun 10 – Jun 24
Cucumbers, squashSow outdoors · Jun 10 – Jun 24
Fall lettuce, spinachSow outdoors · Jul 20 – Aug 3
GarlicPlant cloves · Aug 31 – Oct 5
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jun 3) and first fall frost (Sep 14) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 96084 came on Feb 13 — 13 days earlier than the 1991–2020 average (Feb 26).

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 Round Mountain, CA

The soil mapped at the center of ZIP 96084 is Windy — stony sandy loam, well drained.

TextureStony sandy loamdrains and warms fast; dries out and needs more feeding
pH5.5moderately acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter11.5%high
Hydrologic groupAwater soaks in fast
Farmland classNot prime farmlandUSDA classification

Map unit: Windy and McCarthy stony sandy loams, 0 to 30 percent slopes.

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 96084; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Round Mountain, CA

Summer high90 °Faverage high, July
Winter low22 °Faverage low, December
Hot days49days a year at 90 °F or more
Freezing nights178nights a year at 32 °F or less
Growing degree days2,014base 50 °F — the season’s usable heat
Longest day15 h 06 mindaylight on June 21
Shortest day9 h 15 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation60.3 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 45 °F, low 23 °F 45°23° JanFebruary: average high 49 °F, low 24 °F 49°24° FebMarch: average high 55 °F, low 27 °F 55°27° MarApril: average high 62 °F, low 31 °F 62°31° AprMay: average high 72 °F, low 37 °F 72°37° MayJune: average high 81 °F, low 42 °F 81°42° JunJuly: average high 90 °F, low 48 °F 90°48° JulAugust: average high 88 °F, low 44 °F 88°44° AugSeptember: average high 82 °F, low 38 °F 82°38° SepOctober: average high 68 °F, low 30 °F 68°30° OctNovember: average high 52 °F, low 26 °F 52°26° NovDecember: average high 44 °F, low 22 °F 44°22° Dec

Precipitation by month inches

0″2″4″6″8″10″January: 10.30 in precipitation 10.3 JanFebruary: 9.67 in precipitation 9.7 FebMarch: 9.15 in precipitation 9.2 MarApril: 5.45 in precipitation 5.5 AprMay: 3.44 in precipitation 3.4 MayJune: 1.12 in precipitation 1.1 JunJuly: 0.09 in precipitation 0.1 JulAugust: 0.29 in precipitation 0.3 AugSeptember: 0.41 in precipitation 0.4 SepOctober: 3.56 in precipitation 3.6 OctNovember: 6.20 in precipitation 6.2 NovDecember: 10.62 in precipitation 10.6 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Burney, CA (12 mi away); precipitation: Round Mountain, CA (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

4 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

960659a
Montgomery Creek, CA · 8 mi
960699a
Oak Run, CA · 11 mi
960969a
Whitmore, CA · 11 mi
960089b
Bella Vista, CA · 14 mi
960137b
Burney, CA · 15 mi
960709a
Obrien, CA · 18 mi
960118b
Big Bend, CA · 18 mi
960889b
Shingletown, CA · 20 mi

California planting zones →

Questions about 96084

What planting zone is ZIP code 96084?

ZIP code 96084 (Round Mountain, CA) is in USDA hardiness zone 9a on the 2023 map: the coldest night of an average winter reaches 20 to 25 °F (−6.7 to −3.9 °C).

When is the last frost in Round Mountain, CA?

The median last spring frost (32 °F) near 96084 is June 3; after June 19 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Burney station.

When is the first frost in Round Mountain, CA?

The median first fall frost near 96084 is September 14, giving a median frost-free growing season of 102 days.

When should I plant tomatoes in 96084?

Start tomato seeds indoors around Apr 8 – Apr 22 and set transplants outside around Jun 10 – Jun 24, one to three weeks after the median last frost.

How much rain and snow does 96084 get?

About 60.3 inches of precipitation a year (NOAA 1991–2020 normals, Round Mountain station).

How hot do summers get in Round Mountain, CA?

The average high peaks at 90 °F in July, with about 49 days a year at 90 °F or more.

What kind of soil does 96084 have?

The USDA soil survey maps Windy at the center of ZIP 96084: stony sandy loam, well drained, pH about 5.5 (moderately acidic).

Did spring come early in Round Mountain, CA in 2026?

Spring leaf-out near 96084 came on Feb 13 in 2026, 13 days earlier than the 1991–2020 average (Feb 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Round Mountain, CA?

Long-day onions: the longest day near 96084 is 15 h 06 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).