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Place guide

Planting zones in Chico, CA

This metro spans USDA zones 8b to 9b, so there is no single zone for Chico, CA and anyone who gives you one is rounding. 65% of its ZIP codes are zone 9b; the rest are not.

USDA zones 8b–9b 3 zones across 20 ZIP codes
ZIP codes 20 20 have a NOAA station within range
Weather stations 7 NOAA 1991–2020 normals, across 1,637 sq mi

Your ZIP code

Get the exact answer for your address

Everything above describes Chico, CA as a whole. Hardiness zones and freeze dates are published per ZIP code, so yours is exact β€” enter it and this page will tell you your zone, which NOAA station it comes from and how far away that station is.

Works for all 40,502 US ZIP codes. Freeze dates need a NOAA station within 100 km; where there is none, the page says so rather than estimating one.

Chico, CA does not have one planting answer

Its own weather stations disagree about 28 of the 32 crops in this table right now, so any single list would be wrong for part of the metro area. That is not a gap in the data β€” it is what the data says.

Shortest season
174 days
STRAWBERRY VALLEY, CA US (USC00048606)
Longest season
321 days
OROVILLE, CA US (USC00046521)

147 days of growing season separate those two stations, and both serve ZIP codes in Chico, CA. The ZIP lookup above answers for one address instead of averaging a place that has no average.

Why the hardiness zone does not settle this

A USDA zone is a winter-minimum statistic. It was never a growing-season one, and it does not behave like one: within a single zone the growing season runs a median 54 days wider at the 10th–90th percentile, and annual growing degree days vary by 2.02Γ—.

The zones also overlap rather than stack β€” 30% of zone 6b freezes before the median zone 6a station. The zone tells you what survives your winter; the station tells you what finishes before your autumn.

The whole dataset behind that β†’

Growing season across Chico, CA A one-year bar. Every one of the 7 NOAA stations serving this metro area counts May 4 to October 30 as growing season, 179 days. At least one counts January 29 to December 18, 323 days. The same figures are written out below this chart. JFMAMJJASONDMay 4October 30

All 7 stations agreeAt least one station

Every one of the 7 NOAA stations serving this metro area counts May 4 – October 30 as growing season (179 days). Widening to any single station gives January 29 – December 18 (323 days).

That is a 144-day difference inside one metro area β€” which is why this page gives ranges rather than a single planting date. The ZIP lookup above resolves it to one station.

Which zone you are in depends where you are

Chico, CA covers 3 hardiness zones. A guide that gives the metro one zone has picked whichever is largest and rounded everyone else into it β€” which is fine for the 65% in zone 9b and wrong for the other 35%. Here is the actual split.

Zone ZIP codes Share  
9b 13 65%
9a 5 25%
8b 2 10%

Zones are published per ZIP code, so yours is exact even though the metro's is not. The hardiness tool will tell you which one you are in.

Your freeze dates

Last spring freeze January 29 – May 4
First fall freeze October 30 – December 18

Those are the earliest and latest medians among the 7 stations serving this metro β€” not an average, and not one station standing in for the rest. Half of years freeze later than a station's own median.

The spread is the point. Even in a metro that is one hardiness zone throughout, its stations disagree about the last spring freeze. Hardiness zone and frost date measure different things β€” a zone is the average annual coldest night, a freeze date is when the season turns β€” and a place can be uniform in one and varied in the other. Use the tools below with your own ZIP rather than the ends of this range.

Your growing season

NOAA publishes a growing-season length for each station, and across the 7 stations serving Chico, CA it runs 174–321 days . That figure is published, not computed from the two freeze dates β€” subtracting one from the other gives the wrong answer wherever a season crosses New Year. Mean summer high (June–August) runs 82–95 Β°F , at or above the 90 Β°F point where cool-season crops bolt and tomato and pepper pollen fails β€” so midsummer sowings of lettuce and its relatives are worth holding here. Summer rain over the same months runs 0.4–1.4" across those 7 stations, against the rough inch a week β€” about 13 inches over the same 92 days β€” that a vegetable garden is usually reckoned to want. The middle station covers about 6% of it, so a summer garden here is watered rather than rained on. The inches are NOAA's published normals; the inch a week is a rule of thumb, and it takes no account of a 91 Β°F summer afternoon drying the soil faster than a cool one.

When to start seeds in Chico, CA

Every spring job for 63 crop dates, counted from this metro's own last spring freeze. Each is a range across all 7 stations β€” the earliest and latest that job falls anywhere in the metro β€” because no one station speaks for the whole area.

Crop Job When Offset
Arugula Direct sow January 1 – April 6 4 weeks before
Baby Salad Greens Direct sow January 1 – April 6 4 weeks before
Beets Direct sow January 1 – April 6 4 weeks before
Green Onions Direct sow January 1 – April 6 4 weeks before
Mustard Greens Direct sow January 1 – April 6 4 weeks before
Okra Start indoors January 1 – April 6 4 weeks before
Radishes Direct sow January 1 – April 6 4 weeks before
Turnips Direct sow January 1 – April 6 4 weeks before
Bok Choy Start indoors January 3 – December 26 5 weeks before
Kohlrabi Start indoors January 3 – December 26 5 weeks before
Swiss Chard Start indoors January 3 – December 26 5 weeks before
Green Onions Start indoors January 7 – December 13 8 weeks before
Peppers Start indoors January 7 – December 13 8 weeks before
Cabbage Set out January 8 – April 13 3 weeks before
Carrots Direct sow January 8 – April 13 3 weeks before
Collards Direct sow January 8 – April 13 3 weeks before
Collards Set out January 8 – April 13 3 weeks before
Cucumbers Start indoors January 8 – April 13 3 weeks before
Green Onions Set out January 8 – April 13 3 weeks before
Kale Direct sow January 8 – April 13 3 weeks before
Kale Set out January 8 – April 13 3 weeks before
Kohlrabi Direct sow January 8 – April 13 3 weeks before
Kohlrabi Set out January 8 – April 13 3 weeks before
Leaf Lettuce Direct sow January 8 – April 13 3 weeks before
Pumpkins Start indoors January 8 – April 13 3 weeks before
Summer Squash Start indoors January 8 – April 13 3 weeks before
Winter Squash Start indoors January 8 – April 13 3 weeks before
Zucchini Start indoors January 8 – April 13 3 weeks before
Bok Choy Direct sow January 15 – April 20 2 weeks before
Bok Choy Set out January 15 – April 20 2 weeks before
Broccoli Set out January 15 – April 20 2 weeks before
Cilantro Direct sow January 15 – April 20 2 weeks before
Leaf Lettuce Set out January 15 – April 20 2 weeks before
Swiss Chard Direct sow January 15 – April 20 2 weeks before
Swiss Chard Set out January 15 – April 20 2 weeks before
Broccoli Start indoors January 21 – December 27 6 weeks before
Cabbage Start indoors January 21 – December 27 6 weeks before
Collards Start indoors January 21 – December 27 6 weeks before
Kale Start indoors January 21 – December 27 6 weeks before
Leaf Lettuce Start indoors January 21 – December 27 6 weeks before
Peas Direct sow January 21 – December 27 6 weeks before
Spinach Direct sow January 21 – December 27 6 weeks before
Sweet Potato Start indoors January 21 – December 27 6 weeks before
Tomatoes Start indoors January 21 – December 27 6 weeks before
Dill Direct sow January 22 – April 27 1 week before
Bush Beans Direct sow February 5 – May 11 1 week after
Cucumbers Set out February 5 – May 11 1 week after
Pumpkins Direct sow February 5 – May 11 1 week after
Pumpkins Set out February 5 – May 11 1 week after
Summer Squash Direct sow February 5 – May 11 1 week after
Summer Squash Set out February 5 – May 11 1 week after
Sweet Corn Direct sow February 5 – May 11 1 week after
Tomatoes Set out February 5 – May 11 1 week after
Winter Squash Direct sow February 5 – May 11 1 week after
Winter Squash Set out February 5 – May 11 1 week after
Zucchini Direct sow February 5 – May 11 1 week after
Zucchini Set out February 5 – May 11 1 week after
Cucumbers Direct sow February 12 – May 18 2 weeks after
Okra Direct sow February 12 – May 18 2 weeks after
Okra Set out February 12 – May 18 2 weeks after
Peppers Set out February 12 – May 18 2 weeks after
Southern Peas Direct sow February 12 – May 18 2 weeks after
Sweet Potato Set out February 12 – May 18 2 weeks after

The week offsets are conventional extension guidance and vary by variety; the freeze dates they are counted from are measured. For a single date rather than a range, run when do I start my seeds? with your own ZIP code.

What survives the winter changes across Chico, CA

Of 74 perennial fruits, nuts, berries, vegetables and herbs, 54 come through the winter in zone 8b and only 40 in zone 9b. That is a different garden at each end of the same metro.

Zone ZIPs Survive Fail for being too warm
8b 2 54 of 74 11
9a 5 46 of 74 25
9b 13 40 of 74 32

The last column is the counterintuitive one, and it is why the totals do not simply rise as the winters get milder. Most temperate fruit needs a documented number of hours below about 45 Β°F to break dormancy and set a crop, so an apple fails in a winter that is too warm; currants and rhubarb cook in the summer heat that comes with it. See the full list with reasons.

At least one station here freezes across the new year, which puts the two ends of a spread on opposite sides of the calendar. Drawing it would produce a bar spanning almost the whole year and meaning nothing, so none is drawn.

The 7 stations behind these numbers

The 7 NOAA stations serving Chico, CA A relative sketch of where the stations sit, about 57 kilometres north to south. Each is named with its NOAA identifier in the station list on this page, which carries the same information as text. CHICO UNIV FARM, CA US (USC00041715)DE SABLA, CA US (USC00042402)DOBBINS 1 S, CA US (USC00042456)OROVILLE MUNI AP, CA US (USW00093210)OROVILLE, CA US (USC00046521)PARADISE, CA US (USC00046685)STRAWBERRY VALLEY, CA US (USC00048606) ~57 km north to south

All 7 NOAA stations whose normals this page quotes, spanning about 57 km north to south. Every one is named with its identifier in the station list below β€” this page does not single one out, because no one station speaks for a whole metro area.

A relative sketch, not a map with a projection: longitude is adjusted for latitude so the shape is not stretched, and there is no basemap. For the one station nearest a specific address, with its real distance, use the ZIP lookup above.

Every figure above comes from these, and each is named so you can check it. Which station serves a given ZIP code, and how far away it is, varies across the metro β€” the table below gives it per ZIP code rather than this page averaging it.

Station NOAA ID Last spring freeze First fall freeze Season
Chico Univ Farm, CA USC00041715 March 4 November 17 257 days
De Sabla, CA USC00042402 April 17 November 11 206 days
Dobbins 1 S, CA USC00042456 April 1 November 17 229 days
Oroville Muni AP, CA USW00093210 January 29 December 7 317 days
Oroville, CA USC00046521 January 30 December 13 321 days
Paradise, CA USC00046685 February 7 December 18 313 days
Strawberry Valley, CA USC00048606 May 4 October 30 174 days

These are medians, not averages β€” NOAA publishes freeze dates as a probability distribution, and half of years freeze later than the date shown.

Every ZIP code in Chico, CA

Zones are published per ZIP code, not per metro area, so this is the exact answer rather than the metro area's average. The station column is the nearest one to that ZIP code's centroid and how far away it is β€” the same figure the tools use, shown here so you can see which ZIP codes are well covered and which are reaching.

ZIP code USDA zone Nearest NOAA station Distance
95914 9b Dobbins 1 S, CA 16.3 km
95916 9b Oroville, CA 20.9 km
95917 9b Oroville Muni AP, CA 13.9 km
95926 9b Chico Univ Farm, CA 6.4 km
95928 9b Chico Univ Farm, CA 1.7 km
95929 9a Chico Univ Farm, CA 4.6 km
95930 9a Strawberry Valley, CA 4.7 km
95938 9a Chico Univ Farm, CA 9.9 km
95941 9a Strawberry Valley, CA 15.1 km
95942 9a De Sabla, CA 6.9 km
95948 9b Oroville Muni AP, CA 21.3 km
95954 8b De Sabla, CA 3.4 km
95958 9b Chico Univ Farm, CA 14.2 km
95965 9b Oroville, CA 8.8 km
95966 9b Oroville, CA 12.8 km
95968 9b Oroville Muni AP, CA 8.4 km
95969 9b Paradise, CA 3.9 km
95973 9b Chico Univ Farm, CA 20.9 km
95974 9b Oroville Muni AP, CA 11.8 km
95978 8b De Sabla, CA 8.0 km

ZIP-code positions are area centroids, so a large rural ZIP code's listed distance is measured from the middle of its area rather than from any particular address in it.

Your own ZIP

Work out your own dates

Each of these takes a ZIP code and answers for that ZIP alone, citing the station it used and how far away it is. There is a ZIP box in the header of every page.

Other places to compare

These metros span exactly the same zones β€” 8b–9b β€” so the same plants are in and out of range across them. The freeze dates and the spring calendar are their own.

Gardening in California β€” zones 5b– 11a covers the whole state: how its 1,788 ZIP codes divide between 12 hardiness zones, and the freeze dates across every NOAA station in it.

Other metro areas in CA:

All 388 metro areas, by state

Gear

If you want to act on this

Each link opens an Amazon search rather than a product we picked. We have not tested these and do not rank them β€” the search is the honest version, and you choose.

As an Amazon Associate we earn from qualifying purchases. That costs you nothing extra, and it buys no influence over anything on this site: the dates come from NOAA normals and the zones from the USDA, and no product affects either.

Sources

Where these numbers come from

The hardiness zone is the USDA 2023 Plant Hardiness Zone Map, published per ZIP code by PRISM at Oregon State. The freeze dates are NOAA's 1991–2020 Climate Normals, read from every station whose normals cover a ZIP code in this metro. Nothing here is estimated, and no station stands in for another.

This page names no single station on purpose. Picking one to represent a metro sounds reasonable and is not: the station serving the most ZIP codes is an artifact of where ZIP centroids happen to fall, and it selects a lock on the Monongahela for Pittsburgh and a far southern suburb for Chicago. A range across every station is true; a single cited date for a whole metro is not.

All metro areas