USDA Hardiness Zone 7b
Frost Dates for 37830 — Oak Ridge, Tennessee
Averages from Oak Ridge Atdd, Tn US, the nearest reporting station, 1.4 miles away.
Plant tender crops after April 5, and expect the first autumn freeze around November 1. That leaves about 210 frost-free days.
- Last spring frost
- April 5
- First fall frost
- November 1
- Growing season
- 210 days
- Hardiness zone
- 7b
50% probability
50% probability
frost-free
5 to 10°F annual low
Planting calendar for 37830
| When | What to do |
|---|---|
| January 25 – February 8 | Start peppers and aubergines indoors They need eight to ten weeks under lights before they can go out. |
| February 8 – February 22 | Start tomatoes indoors Six to eight weeks gives a transplant big enough to set fruit early. |
| March 8 – March 22 | Sow peas, spinach, lettuce, radish outdoors These tolerate light frost and prefer to germinate in cool soil. |
| April 5 onward | Transplant tomatoes, peppers, basil, squash, cucumbers The average last freeze has passed — still watch the actual forecast. |
| by August 9 | Sow the autumn crop of carrots, beets and brassicas They need about twelve weeks to size up before growth stops. |
| by October 18 | Harvest tender crops, or be ready to cover them A first freeze two weeks early is well within normal variation. |
| November 1 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 April 5 to put tender plants — tomatoes, peppers, basil, squash — in the ground. That is the date by which half of years in Oak Ridge, Tennessee are past their last freeze. Harvest before November 1, which leaves roughly 210 frost-free days.
ZIP 37830 sits in USDA hardiness zone 7b, meaning the average coldest night of the year falls between 5 to 10°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.