When to plant bell peppers in Montana
Montana’s average last spring frost is May 15, and the first fall frost typically arrives around September 15 — about 123 frost-free days (USDA zones 3a, 3b, 4a, 4b, 5a, 5b, 6a). Bell Pepper needs 60–90 days to mature, which fits comfortably within Montana's growing season.
Montana covers a wide range of climates, so your exact frost dates may differ from the state average by two weeks or more. For dates tuned to your town, use the calendar generator.
When to plant bell peppers in Montana: the short answer
For a spring planting, plant out May 22 – Jun 8, with seeds started indoors Mar 13 – Mar 27. Wait until the soil is at least 60°F and frost is over.
Windows are ~1–2 week bands around each date. Frost dates are a statewide average from NOAA/NCEI normals; your town may differ by two weeks or more. Calendar year 2026.
How to grow bell peppers in Montana, step by step
- Start seeds indoors (Mar 13 – Mar 27). Sow seeds ¼ inch deep in seed-starting mix under bright light. They take 7-14 days to sprout, fastest in soil around 82°F. Harden seedlings off for a week before they go outside.
- Prepare the bed. They need at least six to eight hours of direct sun a day and loose soil at least 12 inches deep, with a pH between 5.5 and 7.0. Dig in compost before planting.
- Plant out (May 22 – Jun 8). Space plants about 18 inches apart in rows 30 inches apart. It is killed by frost, so nothing goes outside until the danger has passed.
- Water and feed. Give it steady, even moisture, about an inch of water a week from rain or the hose.
- Watch for pests and problems. Pests: aphids, flea beetle, pepper maggot, tomato hornworm. Diseases and disorders: bacterial leaf spot, anthracnose, blossom-end rot (calcium disorder), phytophthora blight.
- Harvest (from about Jul 28 – Aug 27). Bell Pepper takes 60-90 days to reach harvest. Needs warm soil; wait until nights stay above 55 F to transplant. Green peppers are just unripe coloured peppers left another 2-3 weeks.
Figures come from our crop data; dates use Montana’s average frost dates. More in the full bell pepper growing guide.
Bell Pepper planting dates by USDA zone in Montana
Montana spans USDA zones 3a, 3b, 4a, 4b, 5a, 5b, 6a. Colder zones, usually higher or further inland, have a later last spring frost and an earlier first fall frost than the state average, so the bell pepper dates shift with them.
When to plant bell peppers in nearby states
Questions gardeners in Montana ask
When is the best time to plant bell peppers in Montana?
Plant bell pepper transplants outdoors in Montana between May 22 and June 8. That timing is set by Montana's average last spring frost of May 15; Montana spans several climates, so cooler and higher parts of the state run later.
When should I start bell pepper seeds indoors in Montana?
Start seeds indoors between March 13 and March 27, about 8 weeks before the last frost, so the seedlings are ready to plant out from May 22.
What is the latest I can plant bell peppers in Montana?
About July 17. Bell peppers need at least 60 days to mature after transplanting, and frost around September 15 ends the season, so later plantings risk being cut short.
When will bell peppers planted in Montana be ready to harvest?
Planted on time, bell peppers are usually ready from about July 28 to August 27, 60-90 days after transplanting.
When is the last frost in Montana?
On average around May 15, with the first fall frost around September 15 - about 123 frost-free days. Your town may differ by two weeks or more.