Glendora, California, sits in USDA hardiness zone 10a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Expect artichoke, meyer lemon, california poppy, and cabbage to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Even in Glendora, no two yards are alike.
A low spot, a south-facing slope, or a stand of trees moves the frost date and sun across a single Glendora lot. Enter your address and we'll score 1,086 plants against your land's actual soil, sun, and frost.
We read public map data around Glendora — soil, climate, flood, and parcel records. How we handle your address.
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Glendora — the short answer
Glendora, California: USDA zone 10a, no 28°F killing freeze on record — the season is year-round, across 12K acres of city.
- USDA zone
- 10a
- USDA PHZM 2023
- Killing freeze
- None on record
- NOAA RCC ACIS 1991–2020, this town’s own record
- City area
- 12K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. The year-round finding is measured — a 30-year record with no 28°F killing freeze in it — never inferred from missing dates.
Hardiness Zone Range
Zone 10a is Glendora's average, not your lot's — a low corner or a tree line moves it. Against Glendora's no killing freeze on record, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Glendora
Each reading below is measured for Glendora itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Winter hardiness
MeasuredGlendora sits in USDA hardiness zone 10a.
The zone sets which perennials, shrubs, and fruit trees live through an average winter here — a plant rated for a colder zone is a safe bet, one rated warmer needs winter protection or gets treated as an annual.
Match perennials and fruit to the zone before you buy, so nothing you plant is a gamble against the cold.
USDA PHZM 2023
The kind of country Glendora is in
Glendora sits in the Southern California/Northern Baja Coast — EPA Level III, inside the wider Mediterranean California. That is read at Glendora's own centroid rather than borrowed from Los Angeles County.
What Grows in Glendora
Every plant below cleared Glendora's own zone 10a. Each card opens that plant's California profile. How we score.
What's on the federal record near Glendora
Closest first, within ~10 miles of Glendora. Listing isn't leaking, and distance isn't exposure.
- GUSD/GODDARD MIDDLE SCHOOLBrownfields · 950 ft
- 1103 LA FLORA LN LLCBrownfields · 1100 ft
- UNITED METHODIST CHURCH OF GLENDORABrownfields · 1300 ft
- DOLORES REINKEBrownfields · 1800 ft
- PEDERSON, MARYBrownfields · 1900 ft
- CHRIS BROCKBrownfields · 2200 ft
- BURBIDGE, JANNABrownfields · 2300 ft
- JAMES ZIMMERBrownfields · 2300 ft
- MORRIS BEERSBrownfields · 0.6 mi
- LEWIS, LINDA & DAVIDBrownfields · 0.6 mi
- NICHOLAS NAREVSKYBrownfields · 0.6 mi
- ROGER SMITHBrownfields · 0.7 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Glendora's center, not your beds. Run your own address for what's upwind of you specifically.
Environmental Intelligence
The counts behind that headline — every source type on the record near Glendora.
Sources Checked
within ~10 miles of Glendora
Severity Distribution
within ~10 miles of Glendora
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Glendora, Brownfields runs higher than the national average — 4,607 sites within ~10 miles of Glendora. Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Brownfields: Brownfield sites are former commercial or industrial properties where legacy soil contamination (heavy metals, PAHs, petroleum compounds) may persist.
Check EPA brownfield remediation status — many sites have completed cleanup with institutional controls.
Check your specific parcel in Glendora
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,086 plant recommendations.
25+ data sources read at your address, not the Glendora average
Your land is one point inside Glendora
Everything above resolves to Glendora as a whole — one PHZM band and one 28°F frost record, read across 12K acres. Your parcel is one point inside that footprint. Slope, tree cover, a low spot that pools cold air, and what is in the soil are all resolved at the address, and none of them are visible at city scale. That is the honest boundary of this page, and the reason the next step is a reading of your own ground rather than a better local average.
Your Lot vs the Glendora Average
Glendora Average
- ●USDA Zones 10a, averaged across Glendora
- ●One soil character for all of Glendora
- ●State-average frost dates
YOUR Parcel
- ✓Your exact zone, not Glendora's 10a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Glendora
Pull a site-specific report for your exact address in Glendora, California — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Glendora averages can't show:
We read public map data around Glendora — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Glendora average
How we know this about Glendora
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals, with the labelled statewide window where none resolves; boundaries and acreage from US Census TIGER/Line 2025; the contamination records from the federal sources named in their beats above. Soil is not read at city grain anywhere on this page — there is no city-resolution survey in our data, which is why you will find no soil grid here rather than a statewide one wearing a local label. The resolution ledger below names every figure this page inherited.
Common questions about Glendora
Is it too late to plant in Glendora?
No — Glendora has no 28°F killing freeze in the 30-year station record, so the growing season is year-round and there is no last-frost date to wait for. Planting is paced by rainfall, heat and daylength instead of by frost: start heat-lovers any month, and time cool-season crops (lettuce, brassicas, peas) for the cooler, wetter half of the year or for higher ground. Succession sowing every few weeks works all year, so the limit is what you can keep watered and harvested, not the calendar.
When does frost risk typically end in Glendora?
It doesn't — Glendora records no 28°F killing freeze at all across the 1991–2020 station record, so there is no spring frost date to plant after. Cold still matters with elevation: the higher you garden, the cooler the nights, and a few tropical crops sulk below about 60°F even where they never freeze.
How long is the growing season in Glendora?
Year-round — the 1991–2020 station record for Glendora contains no 28°F killing freeze, so there is no season to measure between freezes. What paces planting instead is heat, rainfall and daylength: the hottest, wettest stretch is the hard part for cool-season crops, not winter. Elevation is the one real exception — the higher you garden, the colder the nights get.
Is the soil safe to grow vegetables in Glendora?
The federal record around Glendora runs heavier than most — 5,100 documented sites, mostly Brownfields entries (4,607), the nearest Brownfields record about 0.2 miles out — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
Everything above is measured at Glendora's scale — its 10a band and its no killing freeze on record. Your yard writes its own version of Glendora's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
What this page reads at Glendora’s own scale
6 of the readings below were taken at Glendora's own scale — the 12,486 acres it covers and 5,100 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Glendora's own USDA hardiness band, zones 10aUSDA PHZM 2023
- No 28°F killing freeze in the 30-year station record covering Glendora — a year-round growing seasonNOAA Regional Climate Centers ACIS, 1991-2020
- 5,100 documented contamination sites on the federal record near Glendora, the closest Brownfields record about 0.2 miles out from the town centreFederal environmental registers
- Glendora's boundary and the 12,486 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear Glendora's hardiness zoneGrowable Ground crop-matching engine
- The ecoregion at Glendora's own centroid, the Southern California/Northern Baja CoastUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Glendora's 12,486 acres read through its county's SSURGO summaryfrom Los Angeles County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Los Angeles County
- The growing challenges every California grower plans around — written at state scale, so they stay on the state guidefrom California
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Los Angeles County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Glendora's 12,486 acreswhy one lot differs from the next →
- Which side of Glendora you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 12,486 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.2 miles out, measured from the town centrehow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — measured at your address, and averaged away by any Glendora-wide figureread your own land →
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