Monument Hills, California, sits in USDA hardiness zone 9b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
These conditions suit okra, meyer lemon, california poppy, and artichoke — a starting list any specific site will trim or extend with its own soil, sun, and drainage.
Even in Monument Hills, 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 Monument Hills 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 Monument Hills — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Monument Hills — the short answer
Monument Hills, California: USDA zone 9b, about 334 days between hard freezes, across 3K acres of town.
- USDA zone
- 9b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Jan 17
- Yolo County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 17
- Yolo County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~334
- Yolo County normal — NOAA 1991–2020, nearest to this town
- Town area
- 3K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. No 30-year normal resolves at this town’s own centroid, so the hard-freeze dates are Yolo County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9b is Monument Hills's average, not your lot's — a low corner or a tree line moves it. Against Monument Hills's 334-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Monument Hills
Each reading below is measured for Monument Hills itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsMonument Hills runs about 334 days between hard freezes (read from Yolo County, the closest normal to Monument Hills) — close to year-round growing.
Frost is rarely the limit here; winter plantings are as real as summer ones, and the harder question is which crops shrug off the summer heat.
Grow cool-season crops through the mild winter, and choose heat-tolerant varieties for the summer beds.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredMonument Hills sits in USDA hardiness zone 9b.
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 Monument Hills is in
Monument Hills sits in the Central California Valley — EPA Level III, inside the wider Mediterranean California. That is read at Monument Hills's own centroid rather than borrowed from Yolo County.
What Grows in Monument Hills
Every plant below cleared Monument Hills's own zone 9b and its 334-day season. Each card opens that plant's California profile. How we score.
Is it too late to plant in Monument Hills?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Jan 1; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Jan 17 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 17 — long-season crops need about 90 days of runway, quick greens only 30. And with a calendar this mild, the honest answer is that planting barely stops — winter opens seasons colder regions never see.
What's on the federal record near Monument Hills
Closest first, within ~10 miles of Monument Hills. Listing isn't leaking, and distance isn't exposure.
- JUAN SEIN GARDEN SERVICEBrownfields · 1300 ft
- YOLO COUNTY FLOOD CONTROL & WATER CONSERVATION DISTRICTBrownfields · 2300 ft
- 010N001E33L002MNitrate · 2600 ft
- HARRISON CONCRETE CUTTING INC.Brownfields · 0.5 mi
- GASKILL TRUCKINGBrownfields · 0.6 mi
- ISAACSON EQUIPMENT MAINTENANCE, INC.Brownfields · 0.7 mi
- 010N001E33J001MNitrate · 0.8 mi
- WILD WINGS GOLF COURSEBrownfields · 0.8 mi
- ADVANCED HELICOPTER SERVICESBrownfields · 1.0 mi
- WOODLAND AVIATIONBrownfields · 1.0 mi
- GREGORY FARMSBrownfields · 1.0 mi
- SEMINIS VEGETABLE SEEDSBrownfields · 1.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Monument Hills'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 Monument Hills.
Total Sites
742
within ~10 miles of Monument Hills
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Monument Hills
Severity Distribution
within ~10 miles of Monument Hills
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Monument Hills, Brownfields runs higher than the national average — 558 sites within ~10 miles of Monument Hills. That's not a problem with your land — it's information about it.
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 Monument Hills
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 Monument Hills average
Your land is one point inside Monument Hills
Everything above resolves to Monument Hills as a whole — one PHZM band, read across 3K acres, with hard-freeze dates borrowed from Yolo County’s record because no 30-year normal resolves at this town’s own centroid. 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 town 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 Monument Hills Average
Monument Hills Average
- ●USDA Zones 9b, averaged across Monument Hills
- ●One soil character for all of Monument Hills
- ●Frost dates read at Monument Hills's scale: Jan 17 to Dec 17
YOUR Parcel
- ✓Your exact zone, not Monument Hills's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Monument Hills
Pull a site-specific report for your exact address in Monument Hills, California — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Monument Hills averages can't show:
We read public map data around Monument Hills — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Monument Hills average
How we know this about Monument Hills
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this town’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Yolo County’s record, because none resolves here; 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 town grain anywhere on this page — there is no town-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 Monument Hills
When does frost risk typically end in Monument Hills?
The last hard freeze (28°F) in Monument Hills typically lands around Jan 17, per NOAA 1991–2020 climate normals — earlier than the light-frost dates most charts quote. That marks the hard freeze, not the last light frost — lighter frosts keep biting past it, which is why tender transplants here wait until about Feb 7.
When is the first frost in Monument Hills?
The first hard freeze (28°F) in Monument Hills typically arrives around Dec 17, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Dec 3, so the watching starts about Nov 17 — about 334 days after the spring freeze cleared.
How long is the growing season in Monument Hills?
Measured between 28°F hard freezes, Monument Hills sees about 334 frost-free days — roughly Jan 17 through Dec 17, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 7 to Dec 3, about 299 days.
Is the soil safe to grow vegetables in Monument Hills?
The federal record around Monument Hills is a meaningful one — 742 documented sites, mostly Brownfields entries (558), the nearest Brownfields record about 0.3 miles out — so a soil test before new food beds is a sensible precaution here, not a reason to hold back from growing. Remember that proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what sits where.
How do I protect my plants from frost in Monument Hills?
From about Nov 17 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Dec 17 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Dec 17. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Monument Hills's scale — its 9b band and its 334-day season. Your yard writes its own version of Monument Hills'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 Monument Hills’s own scale
5 of the readings below were taken at Monument Hills's own scale — the 2,552 acres it covers and 742 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Monument Hills's own USDA hardiness band, zones 9bUSDA PHZM 2023
- 742 documented contamination sites on the federal record near Monument Hills, the closest Brownfields record about 0.3 miles out from the town centreFederal environmental registers
- Monument Hills's boundary and the 2,552 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9b and a ~334-day seasonGrowable Ground crop-matching engine
- The ecoregion at Monument Hills's own centroid, the Central California ValleyUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Monument Hills has no normal of its own, so its county's is the closest measured readfrom Yolo County
- Soil character — no town-scale survey exists, so Monument Hills's 2,552 acres read through its county's SSURGO summaryfrom Yolo County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Yolo 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 Yolo County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Monument Hills's 2,552 acreswhy one lot differs from the next →
- Which side of Monument Hills you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,552 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.3 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 Monument Hills-wide figureread your own land →