USDA Hardiness Zone 8b
Frost Dates for 39150 — Port Gibson, Mississippi
Averages from Port Gibson 1 Ne, Ms US, the nearest reporting station, 1.1 miles away.
Plant tender crops after March 17, and expect the first autumn freeze around November 12. That leaves about 241 frost-free days.
- Last spring frost
- March 17
- First fall frost
- November 12
- Growing season
- 241 days
- Hardiness zone
- 8b
50% probability
50% probability
frost-free
15 to 20°F annual low
Planting calendar for 39150
| When | What to do |
|---|---|
| January 6 – January 20 | Start peppers and aubergines indoors They need eight to ten weeks under lights before they can go out. |
| January 20 – February 3 | Start tomatoes indoors Six to eight weeks gives a transplant big enough to set fruit early. |
| February 17 – March 3 | Sow peas, spinach, lettuce, radish outdoors These tolerate light frost and prefer to germinate in cool soil. |
| March 17 onward | Transplant tomatoes, peppers, basil, squash, cucumbers The average last freeze has passed — still watch the actual forecast. |
| by August 20 | Sow the autumn crop of carrots, beets and brassicas They need about twelve weeks to size up before growth stops. |
| by October 29 | Harvest tender crops, or be ready to cover them A first freeze two weeks early is well within normal variation. |
| November 12 onward | Plant garlic, mulch beds, lift tender bulbs Garlic wants a cold spell; bare soil loses structure over winter. |
What these dates mean
Wait until after March 17 to put tender plants — tomatoes, peppers, basil, squash — in the ground. That is the date by which half of years in Port Gibson, Mississippi are past their last freeze. Harvest before November 12, which leaves roughly 241 frost-free days.
ZIP 39150 sits in USDA hardiness zone 8b, meaning the average coldest night of the year falls between 15 to 20°F. Zone decides what survives the winter; frost dates decide when to plant each spring. They are different questions, and a plant can pass one and fail the other.
These are thirty-year NOAA averages for 1991–2020, not a forecast. Any individual year can frost two to three weeks either side of these dates, so check the actual forecast before planting out.