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

Planting zone for 91722 — Covina, CA

ZIP code 91722 (Covina, Los Angeles County) is in USDA zone 10a: the coldest winter night averages 30 to 35 °F.

Where ZIP 91722 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 zone10a

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 10a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Covina, 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

A 32 °F frost doesn't happen here in most winters. At the nearest station (NOAA station Pomona/Fairplex, CA — 8 miles away, elevation 1,001 ft) the median growing season is 354 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 91722 came on Jan 18 — about the same time as the 1991–2020 average (Jan 20).

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 Covina, CA

The soil mapped at the center of ZIP 91722 is Palmview — fine sandy loam, well drained. Much of the area is built over (urban land); this is the natural soil underneath.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding
pH7.1neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2%moderate
Hydrologic groupBwater soaks in moderately
Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Urban land-Palmview-Tujunga complex, 0 to 5 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 91722; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Covina, CA

Summer high92 °Faverage high, August
Winter low42 °Faverage low, December
Hot days71days a year at 90 °F or more
Freezing nights3nights a year at 32 °F or less
Growing degree days5,557base 50 °F — the season’s usable heat
Longest day14 h 26 mindaylight on June 21
Shortest day9 h 53 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation16.7 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°100°32 °FJanuary: average high 68 °F, low 43 °F 68°43° JanFebruary: average high 67 °F, low 45 °F 67°45° FebMarch: average high 72 °F, low 47 °F 72°47° MarApril: average high 76 °F, low 50 °F 76°50° AprMay: average high 78 °F, low 54 °F 78°54° MayJune: average high 84 °F, low 57 °F 84°57° JunJuly: average high 90 °F, low 62 °F 90°62° JulAugust: average high 92 °F, low 63 °F 92°63° AugSeptember: average high 89 °F, low 60 °F 89°60° SepOctober: average high 81 °F, low 54 °F 81°54° OctNovember: average high 74 °F, low 47 °F 74°47° NovDecember: average high 67 °F, low 42 °F 67°42° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 3.78 in precipitation 3.8 JanFebruary: 4.32 in precipitation 4.3 FebMarch: 2.65 in precipitation 2.6 MarApril: 0.68 in precipitation 0.7 AprMay: 0.45 in precipitation 0.5 MayJune: 0.13 in precipitation 0.1 JunJuly: 0.06 in precipitation 0.1 JulAugust: 0.00 in precipitation 0.0 AugSeptember: 0.15 in precipitation 0.1 SepOctober: 0.79 in precipitation 0.8 OctNovember: 1.01 in precipitation 1.0 NovDecember: 2.72 in precipitation 2.7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Pomona/Fairplex, CA (8 mi away); precipitation: Covina City Yard Fc387b, CA (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 10a.

9172310a
Covina, CA · 1 mi
9179110a
West Covina, CA · 3 mi
9179310a
West Covina, CA · 3 mi
9179010a
West Covina, CA · 3 mi
9172410a
Covina, CA · 3 mi
9174010a
Glendora, CA · 3 mi
9170610a
Baldwin Park, CA · 4 mi
9101010a
Duarte, CA · 4 mi

All 3 ZIP codes in Covina → · California planting zones →

Questions about 91722

What planting zone is ZIP code 91722?

ZIP code 91722 (Covina, CA) 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 91722 get?

About 16.7 inches of precipitation a year (NOAA 1991–2020 normals, Covina City Yard Fc387b station).

How hot do summers get in Covina, CA?

The average high peaks at 92 °F in August, with about 71 days a year at 90 °F or more.

What kind of soil does 91722 have?

The USDA soil survey maps Palmview at the center of ZIP 91722: fine sandy loam, well drained, pH about 7.1 (neutral).

Did spring come early in Covina, CA in 2026?

Spring leaf-out near 91722 came on Jan 18 in 2026, about the same as the 1991–2020 average (Jan 20), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Covina, CA?

Intermediate onions: the longest day near 91722 is 14 h 26 min, so day-neutral types bulb best; long-day varieties may not bulb fully.