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

Planting zone for 93528 — Johannesburg, CA

ZIP code 93528 (Johannesburg, Kern County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is March 19 and the first fall frost November 25.

Where ZIP 93528 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 frostMar 19
First frostNov 25
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 Johannesburg, 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 Johannesburg, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMarch 19median — 50% chance of a later frost
Safe for tender plantsApril 13only 10% chance of frost after
First fall frostNovember 25median — 10% chance by Nov 5
Growing season251 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 20 and returns around December 8.

From the NOAA station Randsburg, CA — within 1 mile, elevation 3,570 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 93528

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 5 – Feb 19
SpinachSow outdoors · Feb 5 – Feb 26
Broccoli, cabbageStart indoors · Jan 8 – Jan 22
Broccoli, cabbageTransplant · Feb 26 – Mar 12
Onion setsPlant outdoors · Feb 19 – Mar 5
PotatoesPlant outdoors · Feb 26 – Mar 12
LettuceSow outdoors · Feb 19 – Mar 5
Carrots, beetsSow outdoors · Feb 26 – Mar 12
TomatoesStart indoors · Jan 22 – Feb 5
TomatoesTransplant · Mar 26 – Apr 9
Peppers, eggplantStart indoors · Jan 8 – Jan 22
Peppers, eggplantTransplant · Apr 2 – Apr 16
BeansSow outdoors · Mar 26 – Apr 9
Sweet cornSow outdoors · Mar 26 – Apr 9
Cucumbers, squashSow outdoors · Mar 26 – Apr 9
Fall lettuce, spinachSow outdoors · Sep 30 – Oct 14
GarlicPlant cloves · Nov 11 – Dec 16
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 19) and first fall frost (Nov 25) 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 93528 came on Jan 20 — 12 days earlier than the 1991–2020 average (Feb 1).

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 Johannesburg, CA

The soil mapped at the center of ZIP 93528 is Typic Haplargids — cobbly fine sandy loam, well drained.

TextureCobbly fine sandy loamdrains and warms fast; dries out and needs more feeding
pH7.5slightly alkaline; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter0.2%low — add compost
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Typic Haplargids and Lithic Haplargids; thermic hills and mountains.

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 93528; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Johannesburg, CA

Summer high101 °Faverage high, July
Winter low35 °Faverage low, January
Hot days106days a year at 90 °F or more
Freezing nights33nights a year at 32 °F or less
Growing degree days5,700base 50 °F — the season’s usable heat
Longest day14 h 33 mindaylight on June 21
Shortest day9 h 46 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation6.7 inper year, rain and melted snow
Snowfall2 inper year

Average high and low, by month

20°30°40°50°60°70°80°90°100°110°32 °FJanuary: average high 58 °F, low 35 °F 58°35° JanFebruary: average high 61 °F, low 37 °F 61°37° FebMarch: average high 68 °F, low 41 °F 68°41° MarApril: average high 75 °F, low 46 °F 75°46° AprMay: average high 84 °F, low 54 °F 84°54° MayJune: average high 95 °F, low 63 °F 95°63° JunJuly: average high 101 °F, low 69 °F 101°69° JulAugust: average high 100 °F, low 68 °F 100°68° AugSeptember: average high 92 °F, low 62 °F 92°62° SepOctober: average high 80 °F, low 52 °F 80°52° OctNovember: average high 67 °F, low 42 °F 67°42° NovDecember: average high 57 °F, low 35 °F 57°35° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″January: 1.38 in precipitation, 0.4 in snowfall 1.4 JanFebruary: 1.56 in precipitation, 0.3 in snowfall 1.6 FebMarch: 0.98 in precipitation, 0.6 in snowfall 1.0❄1 MarApril: 0.38 in precipitation 0.4 AprMay: 0.14 in precipitation 0.1 MayJune: 0.03 in precipitation 0.0 JunJuly: 0.23 in precipitation 0.2 JulAugust: 0.19 in precipitation 0.2 AugSeptember: 0.19 in precipitation 0.2 SepOctober: 0.47 in precipitation 0.5 OctNovember: 0.47 in precipitation, 0.1 in snowfall 0.5 NovDecember: 0.69 in precipitation, 0.8 in snowfall 0.7❄1 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Randsburg, CA (within 1 mile); precipitation: Randsburg, CA (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

935589a
Red Mountain, CA · 4 mi
935549a
Randsburg, CA · 7 mi
935558b
Ridgecrest, CA · 15 mi
935568b
Ridgecrest, CA · 17 mi
935198b
Cantil, CA · 18 mi
935048b
California City, CA · 19 mi
935168b
Boron, CA · 25 mi
935058b
California City, CA · 25 mi

California planting zones →

Questions about 93528

What planting zone is ZIP code 93528?

ZIP code 93528 (Johannesburg, 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 Johannesburg, CA?

The median last spring frost (32 °F) near 93528 is March 19; after April 13 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Randsburg station.

When is the first frost in Johannesburg, CA?

The median first fall frost near 93528 is November 25, giving a median frost-free growing season of 251 days.

When should I plant tomatoes in 93528?

Start tomato seeds indoors around Jan 22 – Feb 5 and set transplants outside around Mar 26 – Apr 9, one to three weeks after the median last frost.

How much rain and snow does 93528 get?

About 6.7 inches of precipitation a year and 2 inches of snowfall (NOAA 1991–2020 normals, Randsburg station).

How hot do summers get in Johannesburg, CA?

The average high peaks at 101 °F in July, with about 106 days a year at 90 °F or more.

What kind of soil does 93528 have?

The USDA soil survey maps Typic Haplargids at the center of ZIP 93528: cobbly fine sandy loam, well drained, pH about 7.5 (slightly alkaline).

Did spring come early in Johannesburg, CA in 2026?

Spring leaf-out near 93528 came on Jan 20 in 2026, 12 days earlier than the 1991–2020 average (Feb 1), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Johannesburg, CA?

Intermediate onions: the longest day near 93528 is 14 h 33 min, so day-neutral types bulb best; long-day varieties may not bulb fully.