In zone 8, plant basil outside around April 14, about two weeks after your last spring frost, once the soil is at least 60 °F. Start seeds indoors from February 17 to March 3. Basil is sensitive to cold, so don’t rush it.
Basil dates for your ZIP code
Planting times based on university extension guidance (UNH, Cornell, Purdue, Minnesota, Nebraska and UMass Extension). Frost dates from NOAA 1991–2020 U.S. Climate Normals, nearest weather station. Zones derived from the 2023 USDA Plant Hardiness Zone Map data (PRISM Climate Group, Oregon State University). This is not the official USDA Plant Hardiness Zone Map.
Basil timing in zone 8
| Task | When |
|---|---|
| Start indoors | February 17 – March 3 |
| Transplant outside | April 14 |
| First harvest | April 18 – May 12 |
| Sow again | Every 2 weeks through the warm season |
| Pinch tips and flower buds | All season; heat makes basil flower fast |
| Final harvest | Before nights drop toward 50 °F |
Most of zone 8 sees its last spring frost between March 25 and April 6 (typical March 31) and its first fall frost between October 31 and November 9 (typical November 4). Basil is damaged at temperatures around 50 °F, well above freezing, so it waits until nights are warm. The tool above uses the weather station closest to your ZIP code.
Why basil waits for warm weather
Basil is a tender annual herb that is sensitive to cold. Cold soil and air stunt its growth, and temperatures around 50 °F, well above freezing, can blacken its leaves. That is why it goes outside after the frost-free date, once the soil reaches at least 60 °F.
Best basil varieties for zone 8
Basil thrives in the long, warm seasons of zone 8:
- Genovese basil, the classic sweet basil.
- Thai basil, which handles heat well and has a licorice aroma.
- Lemon basil and purple basils such as Dark Opal and Rubin.
How to plant basil
- Start seeds indoors in a warm spot: they need at least 70 °F and sprout in 5–7 days.
- Grow seedlings in full sun or under lights.
- Transplant after your frost-free date, once the soil is 60 °F or warmer.
- Pinch the stem tips once plants have a few sets of leaves, to make them bushy.
- Sow again every two weeks for a continuous supply.
Zone 8 basil tips
- Plant after the frost-free date, once the soil is at least 60 °F.
- Pinch flower buds constantly. In heat, basil flowers quickly and the leaves get sparse.
- Sow new batches every two weeks to replace plants that tire in midsummer.
- Give afternoon shade in the hottest weeks if plants struggle.
Harvesting basil
Harvest lightly from young plants, then pick individual leaves and stem tips as the plants grow. Regular picking keeps basil bushy and productive. Remove flower buds as soon as they appear. Basil can be harvested about 60–70 days after sowing, and it dries easily for winter use. Avoid refrigerating fresh basil, which darkens the leaves.
Basil planting dates in nearby zones
See dates for every zone on the basil planting guide, or build a full schedule with the planting calendar.
Frequently asked questions
Is it too late to plant basil in zone 8 in May?
No. Your warm season is long, and basil grows fast. Keep sowing every couple of weeks.
Why does my basil keep flowering?
Heat speeds flowering. Pinch off buds as soon as they form, and sow new plants every few weeks.
Can I plant basil before the last frost?
No. Basil is damaged by cold even above freezing. Plant it out after your frost-free date, once the soil is 60 °F.
Should I remove basil flowers?
Yes. Pinch off flower buds as soon as they form so the plant keeps producing leaves.
How do I store fresh basil?
Not in the refrigerator, which turns the leaves dark. Keep stems in water at room temperature for a few days, or dry the leaves.
Sources. Planting dates use the median frost dates of each USDA zone, calculated from NOAA climate data for every ZIP code in the zone.