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Place guide

Planting zones in Bloomington, IL

This metro spans USDA zones 5b to 6a, so there is no single zone for Bloomington, IL and anyone who gives you one is rounding. 88% of its ZIP codes are zone 6a; the rest are not.

USDA zones 5b–6a 2 zones across 24 ZIP codes
ZIP codes 24 24 have a NOAA station within range
Weather stations 5 NOAA 1991–2020 normals, across 1,183 sq mi

Your ZIP code

Get the exact answer for your address

Everything above describes Bloomington, IL 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.

The growing season in Bloomington, IL is closing

Nothing in the 32-crop table still has time to mature here. The first fall freeze normally arrives October 15 – October 20 across the 5 NOAA stations serving this metro area .

Your next season already has a date

The first job of it is πŸ§… Green Onions, start indoors, around February 24 – February 28 β€” counted back from a last spring freeze of April 21 – April 25 here.

Every spring date for your ZIP β†’

These are ranges across the whole metro area. The ZIP lookup above gives the dates from your own nearest station instead.

Growing season across Bloomington, IL A one-year bar. Every one of the 5 NOAA stations serving this metro area counts April 25 to October 15 as growing season, 173 days. At least one counts April 21 to October 20, 182 days. The same figures are written out below this chart. JFMAMJJASONDApril 25October 15

All 5 stations agreeAt least one station

Every one of the 5 NOAA stations serving this metro area counts April 25 – October 15 as growing season (173 days). Widening to any single station gives April 21 – October 20 (182 days).

Which zone you are in depends where you are

Bloomington, IL covers 2 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 88% in zone 6a and wrong for the other 12%. Here is the actual split.

Zone ZIP codes Share  
6a 21 88%
5b 3 13%

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 April 21 – April 25
First fall freeze October 15 – October 20

Those are the earliest and latest medians among the 5 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 5 stations serving Bloomington, IL it runs 172–181 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 83–85 Β°F , below the 90 Β°F point where cool-season crops reliably bolt. Summer rain over the same months runs 10.7–12.8" across those 5 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 90% of it, so expect to make up the rest. The inches are NOAA's published normals; the inch a week is a rule of thumb, and it takes no account of a 83 Β°F summer afternoon drying the soil faster than a cool one.

When to start seeds in Bloomington, IL

Every spring job for 63 crop dates, counted from this metro's own last spring freeze. Each is a range across all 5 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
Green Onions Start indoors February 24 – February 28 8 weeks before
Peppers Start indoors February 24 – February 28 8 weeks before
Broccoli Start indoors March 10 – March 14 6 weeks before
Cabbage Start indoors March 10 – March 14 6 weeks before
Collards Start indoors March 10 – March 14 6 weeks before
Kale Start indoors March 10 – March 14 6 weeks before
Leaf Lettuce Start indoors March 10 – March 14 6 weeks before
Peas Direct sow March 10 – March 14 6 weeks before
Spinach Direct sow March 10 – March 14 6 weeks before
Sweet Potato Start indoors March 10 – March 14 6 weeks before
Tomatoes Start indoors March 10 – March 14 6 weeks before
Bok Choy Start indoors March 17 – March 21 5 weeks before
Kohlrabi Start indoors March 17 – March 21 5 weeks before
Swiss Chard Start indoors March 17 – March 21 5 weeks before
Arugula Direct sow March 24 – March 28 4 weeks before
Baby Salad Greens Direct sow March 24 – March 28 4 weeks before
Beets Direct sow March 24 – March 28 4 weeks before
Green Onions Direct sow March 24 – March 28 4 weeks before
Mustard Greens Direct sow March 24 – March 28 4 weeks before
Okra Start indoors March 24 – March 28 4 weeks before
Radishes Direct sow March 24 – March 28 4 weeks before
Turnips Direct sow March 24 – March 28 4 weeks before
Cabbage Set out March 31 – April 4 3 weeks before
Carrots Direct sow March 31 – April 4 3 weeks before
Collards Direct sow March 31 – April 4 3 weeks before
Collards Set out March 31 – April 4 3 weeks before
Cucumbers Start indoors March 31 – April 4 3 weeks before
Green Onions Set out March 31 – April 4 3 weeks before
Kale Direct sow March 31 – April 4 3 weeks before
Kale Set out March 31 – April 4 3 weeks before
Kohlrabi Direct sow March 31 – April 4 3 weeks before
Kohlrabi Set out March 31 – April 4 3 weeks before
Leaf Lettuce Direct sow March 31 – April 4 3 weeks before
Pumpkins Start indoors March 31 – April 4 3 weeks before
Summer Squash Start indoors March 31 – April 4 3 weeks before
Winter Squash Start indoors March 31 – April 4 3 weeks before
Zucchini Start indoors March 31 – April 4 3 weeks before
Bok Choy Direct sow April 7 – April 11 2 weeks before
Bok Choy Set out April 7 – April 11 2 weeks before
Broccoli Set out April 7 – April 11 2 weeks before
Cilantro Direct sow April 7 – April 11 2 weeks before
Leaf Lettuce Set out April 7 – April 11 2 weeks before
Swiss Chard Direct sow April 7 – April 11 2 weeks before
Swiss Chard Set out April 7 – April 11 2 weeks before
Dill Direct sow April 14 – April 18 1 week before
Bush Beans Direct sow April 28 – May 2 1 week after
Cucumbers Set out April 28 – May 2 1 week after
Pumpkins Direct sow April 28 – May 2 1 week after
Pumpkins Set out April 28 – May 2 1 week after
Summer Squash Direct sow April 28 – May 2 1 week after
Summer Squash Set out April 28 – May 2 1 week after
Sweet Corn Direct sow April 28 – May 2 1 week after
Tomatoes Set out April 28 – May 2 1 week after
Winter Squash Direct sow April 28 – May 2 1 week after
Winter Squash Set out April 28 – May 2 1 week after
Zucchini Direct sow April 28 – May 2 1 week after
Zucchini Set out April 28 – May 2 1 week after
Cucumbers Direct sow May 5 – May 9 2 weeks after
Okra Direct sow May 5 – May 9 2 weeks after
Okra Set out May 5 – May 9 2 weeks after
Peppers Set out May 5 – May 9 2 weeks after
Southern Peas Direct sow May 5 – May 9 2 weeks after
Sweet Potato Set out May 5 – May 9 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 Bloomington, IL

Of 74 perennial fruits, nuts, berries, vegetables and herbs, 51 come through the winter in zone 6a and only 48 in zone 5b. That is a different garden at each end of the same metro.

Zone ZIPs Survive Fail for being too warm
5b 3 48 of 74 0
6a 21 51 of 74 0

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.

How certain the freeze dates are in Bloomington, IL Two rows. Each runs from the cautious date, which shortens the growing season, to the optimistic one. The median dates sit between them. Every figure is repeated in the text below this chart. JFMAMJJASONDLast spring freezeFirst fall freeze

Cautious β€” shortens the seasonMedian across stationsOptimistic

Last spring freeze
Plan to May 11 to be careful. Median April 21 – April 25 across 5 stations; April 7 is the optimistic end.
First fall freeze
Plan to September 29 to be careful. Median October 15 – October 20 across 5 stations; November 1 is the optimistic end.

NOAA publishes these as probabilities, not averages β€” the middle figure is a median, so half of years fall either side of it. The cautious end is the 10% tail: in roughly nine years in ten the freeze falls on the safe side of it.

The 5 stations behind these numbers

The 5 NOAA stations serving Bloomington, IL A relative sketch of where the stations sit, about 30 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. BLOOMINGTON 5W, IL US (USC00110764)CHENOA, IL US (USC00111475)CONGERVILLE 2NW, IL US (USC00111836)GIBSON CITY, IL US (USC00113413)NORMAL 4NE, IL US (USC00116200) ~30 km north to south

All 5 NOAA stations whose normals this page quotes, spanning about 30 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
Bloomington 5W, IL USC00110764 April 21 October 20 181 days
Chenoa, IL USC00111475 April 23 October 15 174 days
Congerville 2Nw, IL USC00111836 April 21 October 17 178 days
Gibson City, IL USC00113413 April 21 October 17 178 days
Normal 4Ne, IL USC00116200 April 25 October 16 172 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 Bloomington, IL

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
61701 6a Bloomington 5W, IL 8.0 km
61704 6a Normal 4Ne, IL 8.8 km
61705 6a Bloomington 5W, IL 4.3 km
61720 6a Gibson City, IL 14.4 km
61722 6a Gibson City, IL 22.8 km
61724 6a Gibson City, IL 20.6 km
61726 5b Chenoa, IL 1.2 km
61728 6a Chenoa, IL 19.6 km
61730 6a Normal 4Ne, IL 18.3 km
61731 6a Gibson City, IL 18.5 km
61732 5b Congerville 2Nw, IL 10.6 km
61736 6a Normal 4Ne, IL 18.8 km
61737 6a Normal 4Ne, IL 21.0 km
61744 5b Chenoa, IL 13.7 km
61745 6a Bloomington 5W, IL 21.0 km
61748 6a Normal 4Ne, IL 9.1 km
61752 6a Normal 4Ne, IL 28.5 km
61753 6a Chenoa, IL 13.7 km
61754 6a Bloomington 5W, IL 18.7 km
61761 6a Normal 4Ne, IL 2.4 km
61770 6a Gibson City, IL 12.9 km
61772 6a Bloomington 5W, IL 11.3 km
61774 6a Bloomington 5W, IL 11.0 km
61776 6a Normal 4Ne, IL 7.2 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€” 5b–6a 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 Illinois β€” zones 5a– 7a covers the whole state: how its 1,382 ZIP codes divide between 5 hardiness zones, and the freeze dates across every NOAA station in it.

Other metro areas in IL:

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