Pepper planting guide
When to Plant Peppers After the Last Frost
Move peppers outside after the last frost risk has passed and nighttime lows stay above 50°F. Count back 8–9 weeks from that outdoor date to start seeds indoors.
Quick answer
When should you start pepper seeds and transplant peppers outside?
Start seeds indoors
Count back 8–9 weeks from the day you expect to transplant outdoors. Enter that outdoor date in the calculator below to get your seed-starting window.
Transplant outdoors
Wait until nighttime low temperatures stay above 50°F. Also check the current forecast, because a historical last frost date cannot confirm that a particular night will be warm enough.
Time growing indoors
8–9 weeks
Start seeds indoors this long before the planned outdoor planting day.
Before moving outdoors
Nights above 50°F
Wait until nighttime low temperatures stay above 50°F.
Plant spacing
18 inches
Rows are listed at 30–36 inches apart in the reviewed pepper guide.
Soil pH
6.5–7
Use a soil test before adding phosphorus, potassium or other amendments.
When to transplant peppers outside
Choose an outdoor date after checking both your local frost estimate and nighttime temperatures. Move pepper seedlings outside only after nighttime lows stay above 50°F. The calculator then counts backward from the date you enter.
Estimate my frost dates →Seed-starting calculator
Find when to start seeds indoors
We count backward from the outdoor planting date using university timing guidance.
Why the range is 8–9 weeks
Why this calculator uses 8–9 weeks
The Extension pepper guide says to start seeds about eight weeks before planting outside. Its general indoor seed-starting table keeps peppers indoors for nine weeks. Rather than hide that difference or choose one number, this page shows the combined 8–9 week planning window.
Before transplanting
Introduce seedlings to outdoor conditions gradually
This process is called hardening off. Over one or two weeks, slowly increase outdoor sun exposure, protect seedlings from wind and bring them inside when nights drop below 55°F.
Pepper seed-starting checklist
Sow 1/4 inch deep
Use a clean seed-starting mix without garden soil, and follow the seed packet for your variety.
Keep the seed-starting mix warm
The university guide lists 80–90°F for a heating mat until seedlings emerge and about 70°F as an ideal soil temperature. Heated mix dries faster, so check moisture often.
Provide bright overhead light
Insufficient overhead light can produce elongated, leaning stems. Adjust the setup as seedlings grow.
Delay the final outdoor move
Wait for nighttime lows above 50°F, then transplant in late afternoon or on a cloudy, calm day as the source recommends.
After planting
Keep moisture consistent
The Extension guide links inconsistent moisture with weaker flowers, small fruit and blossom-end rot risk.
Use the tested spacing
Set plants 18 inches apart in rows 30–36 inches apart unless local guidance or the variety requires an adjustment.
Diagnose before treating
Environmental stress, disease, insects and wildlife can look similar. Identify the cause before choosing a treatment.
Plan the dates in the right order
First estimate your local spring frost window. Next choose an outdoor date that also meets the 50°F nighttime requirement. Then use the seed calculator to count back 8–9 weeks.
A practical next step
Plan peppers with your local season
Warm-season crops need more than a frost-free date. Check soil warmth and nighttime temperatures before planting outdoors.
- 1. Local dates
Find spring and fall frost dates
See historical 32°F freeze estimates and the matched NOAA station for your ZIP Code.
- 2. Season length
Estimate the frost-date growing window
Compare cautious, middle and less-cautious spring/fall date pairs.
- 3. Seed schedule
Count backward for indoor seed starting
Choose a suitable outdoor date for peppers, then use the reviewed crop-specific lead time to build a seed schedule.