Place guide
Planting zones in Harrisburg-Carlisle, PA
This metro spans USDA zones 6b to 7a, so there is no single zone for Harrisburg-Carlisle, PA and anyone who gives you one is rounding. 77% of its ZIP codes are zone 7a; the rest are not.
Your ZIP code
Get the exact answer for your address
Everything above describes Harrisburg-Carlisle, PA 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 Harrisburg-Carlisle, PA is closing
Nothing in the 32-crop table still has time to mature here. The first fall freeze normally arrives October 16 – November 2 across the 10 NOAA stations serving this metro area .
Your next season already has a date
The first job of it is 🧅 Green Onions, start indoors, around February 12 – March 6 — counted back from a last spring freeze of April 9 – May 1 here.
These are ranges across the whole metro area. The ZIP lookup above gives the dates from your own nearest station instead.
All 10 stations agreeAt least one station
Every one of the 10 NOAA stations serving this metro area counts May 1 – October 16 as growing season (168 days). Widening to any single station gives April 9 – November 2 (207 days).
That is a 39-day difference inside one metro area — 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
Harrisburg-Carlisle, PA covers 2 hardiness zones. A guide that gives the metro one zone has picked whichever is largest and rounded everyone else into it — which is fine for the 77% in zone 7a and wrong for the other 23%. Here is the actual split.
| Zone | ZIP codes | Share | |
|---|---|---|---|
| 7a | 44 | 77% | |
| 6b | 13 | 23% |
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
Those are the earliest and latest medians among the 10 stations serving this metro — 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 — a zone is the average annual coldest night, a freeze date is when the season turns — 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 10 stations serving Harrisburg-Carlisle, PA it runs 168–206 days . That figure is published, not computed from the two freeze dates — subtracting one from the other gives the wrong answer wherever a season crosses New Year. Mean summer high (June–August) runs 81–85 °F , below the 90 °F point where cool-season crops reliably bolt. Summer rain over the same months runs 11.2–14.2" across those 10 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 95% 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 °F summer afternoon drying the soil faster than a cool one.
When to start seeds in Harrisburg-Carlisle, PA
Every spring job for 63 crop dates, counted from this metro's own last spring freeze. Each is a range across all 10 stations — the earliest and latest that job falls anywhere in the metro — because no one station speaks for the whole area.
| Crop | Job | When | Offset |
|---|---|---|---|
| Green Onions | Start indoors | February 12 – March 6 | 8 weeks before |
| Peppers | Start indoors | February 12 – March 6 | 8 weeks before |
| Broccoli | Start indoors | February 26 – March 20 | 6 weeks before |
| Cabbage | Start indoors | February 26 – March 20 | 6 weeks before |
| Collards | Start indoors | February 26 – March 20 | 6 weeks before |
| Kale | Start indoors | February 26 – March 20 | 6 weeks before |
| Leaf Lettuce | Start indoors | February 26 – March 20 | 6 weeks before |
| Peas | Direct sow | February 26 – March 20 | 6 weeks before |
| Spinach | Direct sow | February 26 – March 20 | 6 weeks before |
| Sweet Potato | Start indoors | February 26 – March 20 | 6 weeks before |
| Tomatoes | Start indoors | February 26 – March 20 | 6 weeks before |
| Bok Choy | Start indoors | March 5 – March 27 | 5 weeks before |
| Kohlrabi | Start indoors | March 5 – March 27 | 5 weeks before |
| Swiss Chard | Start indoors | March 5 – March 27 | 5 weeks before |
| Arugula | Direct sow | March 12 – April 3 | 4 weeks before |
| Baby Salad Greens | Direct sow | March 12 – April 3 | 4 weeks before |
| Beets | Direct sow | March 12 – April 3 | 4 weeks before |
| Green Onions | Direct sow | March 12 – April 3 | 4 weeks before |
| Mustard Greens | Direct sow | March 12 – April 3 | 4 weeks before |
| Okra | Start indoors | March 12 – April 3 | 4 weeks before |
| Radishes | Direct sow | March 12 – April 3 | 4 weeks before |
| Turnips | Direct sow | March 12 – April 3 | 4 weeks before |
| Cabbage | Set out | March 19 – April 10 | 3 weeks before |
| Carrots | Direct sow | March 19 – April 10 | 3 weeks before |
| Collards | Direct sow | March 19 – April 10 | 3 weeks before |
| Collards | Set out | March 19 – April 10 | 3 weeks before |
| Cucumbers | Start indoors | March 19 – April 10 | 3 weeks before |
| Green Onions | Set out | March 19 – April 10 | 3 weeks before |
| Kale | Direct sow | March 19 – April 10 | 3 weeks before |
| Kale | Set out | March 19 – April 10 | 3 weeks before |
| Kohlrabi | Direct sow | March 19 – April 10 | 3 weeks before |
| Kohlrabi | Set out | March 19 – April 10 | 3 weeks before |
| Leaf Lettuce | Direct sow | March 19 – April 10 | 3 weeks before |
| Pumpkins | Start indoors | March 19 – April 10 | 3 weeks before |
| Summer Squash | Start indoors | March 19 – April 10 | 3 weeks before |
| Winter Squash | Start indoors | March 19 – April 10 | 3 weeks before |
| Zucchini | Start indoors | March 19 – April 10 | 3 weeks before |
| Bok Choy | Direct sow | March 26 – April 17 | 2 weeks before |
| Bok Choy | Set out | March 26 – April 17 | 2 weeks before |
| Broccoli | Set out | March 26 – April 17 | 2 weeks before |
| Cilantro | Direct sow | March 26 – April 17 | 2 weeks before |
| Leaf Lettuce | Set out | March 26 – April 17 | 2 weeks before |
| Swiss Chard | Direct sow | March 26 – April 17 | 2 weeks before |
| Swiss Chard | Set out | March 26 – April 17 | 2 weeks before |
| Dill | Direct sow | April 2 – April 24 | 1 week before |
| Bush Beans | Direct sow | April 16 – May 8 | 1 week after |
| Cucumbers | Set out | April 16 – May 8 | 1 week after |
| Pumpkins | Direct sow | April 16 – May 8 | 1 week after |
| Pumpkins | Set out | April 16 – May 8 | 1 week after |
| Summer Squash | Direct sow | April 16 – May 8 | 1 week after |
| Summer Squash | Set out | April 16 – May 8 | 1 week after |
| Sweet Corn | Direct sow | April 16 – May 8 | 1 week after |
| Tomatoes | Set out | April 16 – May 8 | 1 week after |
| Winter Squash | Direct sow | April 16 – May 8 | 1 week after |
| Winter Squash | Set out | April 16 – May 8 | 1 week after |
| Zucchini | Direct sow | April 16 – May 8 | 1 week after |
| Zucchini | Set out | April 16 – May 8 | 1 week after |
| Cucumbers | Direct sow | April 23 – May 15 | 2 weeks after |
| Okra | Direct sow | April 23 – May 15 | 2 weeks after |
| Okra | Set out | April 23 – May 15 | 2 weeks after |
| Peppers | Set out | April 23 – May 15 | 2 weeks after |
| Southern Peas | Direct sow | April 23 – May 15 | 2 weeks after |
| Sweet Potato | Set out | April 23 – May 15 | 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 Harrisburg-Carlisle, PA
Of 74 perennial fruits, nuts, berries, vegetables and herbs, 58 come through the winter in zone 7a and only 51 in zone 6b. That is a different garden at each end of the same metro.
| Zone | ZIPs | Survive | Fail for being too warm |
|---|---|---|---|
| 6b | 13 | 51 of 74 | 0 |
| 7a | 44 | 58 of 74 | 1 |
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 °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.
Cautious — shortens the seasonMedian across stationsOptimistic
- Last spring freeze
- Plan to May 20 to be careful. Median April 9 – May 1 across 10 stations; March 27 is the optimistic end.
- First fall freeze
- Plan to October 3 to be careful. Median October 16 – November 2 across 10 stations; November 15 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 10 stations behind these numbers
All 10 NOAA stations whose normals this page quotes, spanning about 94 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 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 — the table below gives it per ZIP code rather than this page averaging it.
| Station | NOAA ID | Last spring freeze | First fall freeze | Season |
|---|---|---|---|---|
| Biglerville, PA | USC00360656 | April 15 | October 27 | 194 days |
| Bloserville 1 N, PA | USC00360763 | April 18 | October 26 | 191 days |
| Carlisle Wtp, PA | USC00361920 | April 23 | October 18 | 177 days |
| Dehart Dam, PA | USC00362071 | May 1 | October 16 | 168 days |
| Harrisburg 1 NE, PA | USC00363698 | April 15 | October 23 | 189 days |
| Harrisburg Cptl Cy AP, PA | USW00014751 | April 9 | November 1 | 205 days |
| Lewistown, PA | USC00364992 | April 21 | October 24 | 185 days |
| Middletown Harrisburg INTL AP, PA | USW00014711 | April 9 | November 2 | 206 days |
| Selinsgrove 2 S, PA | USC00367931 | April 25 | October 22 | 178 days |
| Shippensburg, PA | USC00368073 | April 19 | October 24 | 188 days |
These are medians, not averages — NOAA publishes freeze dates as a probability distribution, and half of years freeze later than the date shown.
Every ZIP code in Harrisburg-Carlisle, PA
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 — 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 |
|---|---|---|---|
| 17005 | 6b | Dehart Dam, PA | 16.7 km |
| 17006 | 7a | Bloserville 1 N, PA | 13.5 km |
| 17007 | 7a | Carlisle Wtp, PA | 11.4 km |
| 17011 | 7a | Harrisburg Cptl Cy AP, PA | 6.9 km |
| 17013 | 7a | Carlisle Wtp, PA | 1.8 km |
| 17015 | 7a | Carlisle Wtp, PA | 5.9 km |
| 17018 | 7a | Dehart Dam, PA | 7.8 km |
| 17020 | 7a | Harrisburg 1 NE, PA | 20.7 km |
| 17023 | 6b | Dehart Dam, PA | 14.4 km |
| 17024 | 7a | Bloserville 1 N, PA | 16.7 km |
| 17025 | 7a | Harrisburg 1 NE, PA | 8.9 km |
| 17027 | 7a | Harrisburg Cptl Cy AP, PA | 12.9 km |
| 17030 | 6b | Dehart Dam, PA | 16.4 km |
| 17032 | 6b | Dehart Dam, PA | 6.6 km |
| 17033 | 7a | Middletown Harrisburg INTL AP, PA | 14.2 km |
| 17034 | 7a | Middletown Harrisburg INTL AP, PA | 2.5 km |
| 17036 | 7a | Middletown Harrisburg INTL AP, PA | 8.1 km |
| 17037 | 6b | Bloserville 1 N, PA | 19.5 km |
| 17040 | 7a | Bloserville 1 N, PA | 4.2 km |
| 17043 | 7a | Harrisburg 1 NE, PA | 4.5 km |
| 17045 | 6b | Selinsgrove 2 S, PA | 23.8 km |
| 17047 | 7a | Bloserville 1 N, PA | 12.6 km |
| 17048 | 6b | Dehart Dam, PA | 14.3 km |
| 17050 | 7a | Carlisle Wtp, PA | 13.7 km |
| 17053 | 7a | Harrisburg 1 NE, PA | 14.1 km |
| 17055 | 7a | Harrisburg Cptl Cy AP, PA | 13.2 km |
| 17057 | 7a | Middletown Harrisburg INTL AP, PA | 3.1 km |
| 17061 | 7a | Dehart Dam, PA | 17.2 km |
| 17062 | 6b | Lewistown, PA | 32.5 km |
| 17065 | 7a | Biglerville, PA | 15.3 km |
| 17068 | 7a | Carlisle Wtp, PA | 19.3 km |
| 17069 | 7a | Dehart Dam, PA | 19.6 km |
| 17071 | 7a | Bloserville 1 N, PA | 21.5 km |
| 17074 | 7a | Carlisle Wtp, PA | 28.4 km |
| 17080 | 6b | Selinsgrove 2 S, PA | 16.6 km |
| 17081 | 7a | Carlisle Wtp, PA | 8.4 km |
| 17090 | 7a | Carlisle Wtp, PA | 10.3 km |
| 17093 | 7a | Harrisburg 1 NE, PA | 5.8 km |
| 17097 | 6b | Dehart Dam, PA | 14.0 km |
| 17098 | 6b | Dehart Dam, PA | 17.5 km |
| 17101 | 7a | Harrisburg 1 NE, PA | 3.2 km |
| 17102 | 7a | Harrisburg 1 NE, PA | 3.1 km |
| 17103 | 7a | Harrisburg 1 NE, PA | 1.0 km |
| 17104 | 7a | Harrisburg 1 NE, PA | 3.0 km |
| 17109 | 7a | Harrisburg 1 NE, PA | 4.0 km |
| 17110 | 7a | Harrisburg 1 NE, PA | 4.9 km |
| 17111 | 7a | Harrisburg 1 NE, PA | 7.7 km |
| 17112 | 7a | Dehart Dam, PA | 9.8 km |
| 17113 | 7a | Harrisburg Cptl Cy AP, PA | 2.9 km |
| 17120 | 7a | Harrisburg 1 NE, PA | 2.1 km |
| 17240 | 7a | Shippensburg, PA | 11.3 km |
| 17241 | 7a | Bloserville 1 N, PA | 9.9 km |
| 17257 | 7a | Shippensburg, PA | 2.1 km |
| 17266 | 7a | Shippensburg, PA | 9.8 km |
| 17324 | 7a | Biglerville, PA | 10.7 km |
| 17978 | 6b | Dehart Dam, PA | 19.1 km |
| 17980 | 6b | Dehart Dam, PA | 10.9 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.
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What survives my winter?
Runs on the hardiness zone, so it answers for all of Harrisburg-Carlisle, PA at once — zone across 74 perennial fruits, berries, vegetables and herbs.
- When do I start my seeds?
Dates every spring job from your own last freeze — sow indoors, set out, direct sow.
- When do I sow the next round?
How often each crop is worth re-sowing, and when the next sowing is due.
- What can I still plant?
Counts the growing days left before your first fall freeze, crop by crop.
Other places to compare
These metros span exactly the same zones — 6b–7a — so the same plants are in and out of range across them. The freeze dates and the spring calendar are their own.
- Springfield, MO — zones 6b–7a
- Reading, PA — zones 6b–7a
- York-Hanover, PA — zones 6b–7a
- Weirton-Steubenville, WV-OH — zones 6b–7a
- Lexington-Fayette, KY — zones 6b–7a
- Winchester, VA-WV — zones 6b–7a
- Cape Girardeau, MO-IL — zones 6b–7a
- Staunton-Stuarts Draft, VA — zones 6b–7a
Gardening in Pennsylvania — zones 5b– 8a covers the whole state: how its 1,793 ZIP codes divide between 6 hardiness zones, and the freeze dates across every NOAA station in it.
Other metro areas in PA:
- Lancaster, PA Zone 7a
- Reading, PA Zones 6b–7a
- Johnstown, PA Zones 6a–6b
- York-Hanover, PA Zones 6b–7a
- Erie, PA Zones 6a–7a
- State College, PA Zones 6a–6b
- Chambersburg, PA Zones 6b–7b
- Williamsport, PA Zones 6a–6b
- Lebanon, PA Zone 7a
- Gettysburg, PA Zones 6b–7a
- Altoona, PA Zone 6b
- Philadelphia-Camden-Wilmington, PA-NJ-DE-MD Zones 6b–8a
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.
- 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 6b, 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
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.