Missouri
Planting zones in Marion County, Missouri
Every ZIP code in this county is USDA zone 6a — so unlike most of the places people look up, there is one right answer here and it holds wherever you are in the county.
Your ZIP code
Get the exact answer for your address
Everything above describes Marion County, Missouri as a whole. Hardiness zones and freeze dates are published per ZIP code, so yours is exact — enter it and this page will tell you your zone, which NOAA station it comes from and how far away that station is.
The growing season in Marion County is closing
Nothing in the 32-crop table still has time to mature here. The first fall freeze normally arrives October 19 – October 30 across the 4 NOAA stations serving this county .
Your next season already has a date
The first job of it is 🧅 Green Onions, start indoors, around February 11 – February 20 — counted back from a last spring freeze of April 8 – April 17 here.
These are ranges across the whole county. The ZIP lookup above gives the dates from your own nearest station instead.
All 4 stations agreeAt least one station
Every one of the 4 NOAA stations serving this county counts April 17 – October 19 as growing season (185 days). Widening to any single station gives April 8 – October 30 (205 days).
Your freeze dates
Across the 4 NOAA stations serving this county. These are medians — half of years freeze later than the date shown — so treat the later end of each range as the cautious one.
The growing season runs 184–204 days depending which station you are nearest, as published by NOAA rather than computed from the dates above. Summer highs average 84–85.4 °F in June–August. Summer rain over the same months runs 11.1–13.7" across those 4 stations, against the rough inch a week — about 13 inches over the same 92 days — that a vegetable garden is usually reckoned to want. The middle station covers about 98% 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 85 °F summer afternoon drying the soil faster than a cool one.
Every ZIP code in Marion County
Zones are published per ZIP code, not per county, so this is the exact answer rather than the county's average. The station column is the nearest one to that ZIP code's centroid and how far away it is — 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 |
|---|---|---|---|
| 63401 | 6a | Hannibal Wtr Wks, MO | 8.7 km |
| 63454 | 6a | Quincy Dam 21, IL | 19.1 km |
| 63456 | 6a | Monroe City, MO | 2.1 km |
| 63461 | 6a | Quincy Dam 21, IL | 15.7 km |
| 63463 | 6a | Steffenville, MO | 16.0 km |
| 63471 | 6a | Quincy Dam 21, IL | 6.4 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.
When to start seeds in Marion County
Every date below is anchored on the last spring freeze at each station and reported as a range across all 4 of them, because no one station speaks for the county.
| Crop | Job | When | Offset |
|---|---|---|---|
| 🧅 Green Onions | Start indoors | February 11 – February 20 | 8 wk before |
| 🌶️ Peppers | Start indoors | February 11 – February 20 | 8 wk before |
| 🥦 Broccoli | Start indoors | February 25 – March 6 | 6 wk before |
| 🥬 Cabbage | Start indoors | February 25 – March 6 | 6 wk before |
| 🥬 Collards | Start indoors | February 25 – March 6 | 6 wk before |
| 🥬 Kale | Start indoors | February 25 – March 6 | 6 wk before |
| 🥬 Leaf Lettuce | Start indoors | February 25 – March 6 | 6 wk before |
| 🫛 Peas | Direct sow | February 25 – March 6 | 6 wk before |
| 🥬 Spinach | Direct sow | February 25 – March 6 | 6 wk before |
| 🍠 Sweet Potato | Start indoors | February 25 – March 6 | 6 wk before |
| 🍅 Tomatoes | Start indoors | February 25 – March 6 | 6 wk before |
| 🥬 Bok Choy | Start indoors | March 4 – March 13 | 5 wk before |
| 🥬 Kohlrabi | Start indoors | March 4 – March 13 | 5 wk before |
| 🥬 Swiss Chard | Start indoors | March 4 – March 13 | 5 wk before |
| 🥬 Arugula | Direct sow | March 11 – March 20 | 4 wk before |
| 🥬 Baby Salad Greens | Direct sow | March 11 – March 20 | 4 wk before |
| 🥕 Beets | Direct sow | March 11 – March 20 | 4 wk before |
| 🧅 Green Onions | Direct sow | March 11 – March 20 | 4 wk before |
| 🥬 Mustard Greens | Direct sow | March 11 – March 20 | 4 wk before |
| 🌶️ Okra | Start indoors | March 11 – March 20 | 4 wk before |
| 🌱 Radishes | Direct sow | March 11 – March 20 | 4 wk before |
| 🥔 Turnips | Direct sow | March 11 – March 20 | 4 wk before |
| 🥬 Cabbage | Set out | March 18 – March 27 | 3 wk before |
| 🥕 Carrots | Direct sow | March 18 – March 27 | 3 wk before |
| 🥬 Collards | Direct sow | March 18 – March 27 | 3 wk before |
| 🥬 Collards | Set out | March 18 – March 27 | 3 wk before |
| 🥒 Cucumbers | Start indoors | March 18 – March 27 | 3 wk before |
| 🧅 Green Onions | Set out | March 18 – March 27 | 3 wk before |
| 🥬 Kale | Direct sow | March 18 – March 27 | 3 wk before |
| 🥬 Kale | Set out | March 18 – March 27 | 3 wk before |
| 🥬 Kohlrabi | Direct sow | March 18 – March 27 | 3 wk before |
| 🥬 Kohlrabi | Set out | March 18 – March 27 | 3 wk before |
| 🥬 Leaf Lettuce | Direct sow | March 18 – March 27 | 3 wk before |
| 🎃 Pumpkins | Start indoors | March 18 – March 27 | 3 wk before |
| 🎃 Summer Squash | Start indoors | March 18 – March 27 | 3 wk before |
| 🎃 Winter Squash | Start indoors | March 18 – March 27 | 3 wk before |
| 🥒 Zucchini | Start indoors | March 18 – March 27 | 3 wk before |
| 🥬 Bok Choy | Direct sow | March 25 – April 3 | 2 wk before |
| 🥬 Bok Choy | Set out | March 25 – April 3 | 2 wk before |
| 🥦 Broccoli | Set out | March 25 – April 3 | 2 wk before |
| 🌿 Cilantro | Direct sow | March 25 – April 3 | 2 wk before |
| 🥬 Leaf Lettuce | Set out | March 25 – April 3 | 2 wk before |
| 🥬 Swiss Chard | Direct sow | March 25 – April 3 | 2 wk before |
| 🥬 Swiss Chard | Set out | March 25 – April 3 | 2 wk before |
| 🌿 Dill | Direct sow | April 1 – April 10 | 1 wk before |
| 🫘 Bush Beans | Direct sow | April 15 – April 24 | 1 wk after |
| 🥒 Cucumbers | Set out | April 15 – April 24 | 1 wk after |
| 🎃 Pumpkins | Direct sow | April 15 – April 24 | 1 wk after |
| 🎃 Pumpkins | Set out | April 15 – April 24 | 1 wk after |
| 🎃 Summer Squash | Direct sow | April 15 – April 24 | 1 wk after |
| 🎃 Summer Squash | Set out | April 15 – April 24 | 1 wk after |
| 🌽 Sweet Corn | Direct sow | April 15 – April 24 | 1 wk after |
| 🍅 Tomatoes | Set out | April 15 – April 24 | 1 wk after |
| 🎃 Winter Squash | Direct sow | April 15 – April 24 | 1 wk after |
| 🎃 Winter Squash | Set out | April 15 – April 24 | 1 wk after |
| 🥒 Zucchini | Direct sow | April 15 – April 24 | 1 wk after |
| 🥒 Zucchini | Set out | April 15 – April 24 | 1 wk after |
| 🥒 Cucumbers | Direct sow | April 22 – May 1 | 2 wk after |
| 🌶️ Okra | Direct sow | April 22 – May 1 | 2 wk after |
| 🌶️ Okra | Set out | April 22 – May 1 | 2 wk after |
| 🌶️ Peppers | Set out | April 22 – May 1 | 2 wk after |
| 🫘 Southern Peas | Direct sow | April 22 – May 1 | 2 wk after |
| 🍠 Sweet Potato | Set out | April 22 – May 1 | 2 wk after |
Offsets are published guidance; the dates they land on are computed from measured NOAA normals. The seed-starting tool does this for your own ZIP code and counts the days.
What lives through a zone 6a winter
Of 74 perennial edibles, 51 come through a zone 6a winter — and 0 fail here for being too warm rather than too cold, needing more winter chill than this county gets or more heat than they tolerate. Among the ones that work: Cranberry, Honeyberry, Lingonberry, Apple, Aronia, Black Currant, Elderberry, Gooseberry.
Hardiness ranges are a judgement, published by growers rather than measured; the zone they are compared against is measured. On a warm-end verdict, check with your local extension service — a coastal zone 8 and an inland zone 8 are not the same summer.
Cautious — shortens the seasonMedian across stationsOptimistic
- Last spring freeze
- Plan to May 4 to be careful. Median April 8 – April 17 across 4 stations; March 24 is the optimistic end.
- First fall freeze
- Plan to September 30 to be careful. Median October 19 – October 30 across 4 stations; November 10 is the optimistic end.
NOAA publishes these as probabilities, not averages — 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 4 stations behind these numbers
All 4 NOAA stations whose normals this page quotes, spanning about 37 km north to south. Every one is named with its identifier in the station list below — this page does not single one out, because no one station speaks for a whole county.
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.
These are the stations this county's ZIP codes actually cite as nearest — not a claim that each one sits inside its boundary, since a rural ZIP legitimately reaches over it. Every figure above comes from them, and each is named so you can check it.
| Station | NOAA ID | Last spring freeze | First fall freeze | Season |
|---|---|---|---|---|
| Hannibal Wtr Wks, MO | USC00233601 | April 10 | October 27 | 199 days |
| Monroe City, MO | USC00235708 | April 12 | October 22 | 190 days |
| Quincy Dam 21, IL | USC00117077 | April 8 | October 30 | 204 days |
| Steffenville, MO | USC00238051 | April 17 | October 19 | 184 days |
These are medians, not averages — NOAA publishes freeze dates as a probability distribution, and half of years freeze later than the date shown.
Your own ZIP
Work out your own dates
This page describes a whole county. Every tool below answers for one ZIP code, which is the grain the underlying data is published at.
Other places to compare
Marion County sits in Missouri. That page carries the whole state's zone spread, its metro areas, and every other county in it with a page here.
More of Missouri
- Monroe County, MO 6a–6b
- Schuyler County, MO 5b–6a
- Ozark County, MO 7a–7b
- Nodaway County, MO 5b–6a
- Taney County, MO 7a
- Texas County, MO 6b–7a
- New Madrid County, MO 7b
- Vernon County, MO 6b–7a
- Barry County, MO 7a
- McDonald County, MO 7a
- Saline County, MO 6b
- Stoddard County, MO 7a–7b
Counties with the same zones — 6a
Matched on the exact zone set, not a dominant zone, so the winter answer on these pages really is the same one as here.
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 — the search is the honest version, and you choose.
- Trunk wrapZone 6a is cold enough that winter sun on a young trunk does more damage than the cold does.
- Row cover and frost clothThe season here closes at the first fall freeze dated above — a cover buys back some of those days at the end.
- MulchFor the perennials nearest their cold limit in zone 6a, where an insulated crown is what decides whether they come back.
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
Hardiness zones are the USDA 2023 Plant Hardiness Zone Map, published per ZIP code by PRISM at Oregon State. Freeze dates and growing-season lengths are NOAA 1991–2020 Climate Normals, taken per station and cited above by name and NOAA ID.
County boundaries come from the Census ZCTA-to-county relation, which is what places each ZIP code — and which treats parishes, boroughs and census areas as county equivalents. No station is chosen to represent this county: every range above is taken across all of them and the count is stated, because picking one would be a judgement dressed as a measurement.