When to plant · 4 cities · zones 4b–5b
When to plant basil in Montana
Start Genovese Basil seeds indoors around Apr 22 and transplant around Jun 3 — the Montana statewide median, counted from a last spring frost of May 20 across 332 ZIP codes and 181 NOAA stations.
The rule: Basil is damaged below about 50 °F, well before frost: transplant two weeks after the last frost, not on it.
Montana basil, by step
Statewide median last frost May 20, first fall frost Sep 22, 2027 season. Each cultivar's own indoor lead time and days to maturity, same engine as the Plan Builder.
| Cultivar | Start indoors | Plant out | First harvest | Days |
|---|---|---|---|---|
| Genovese BasilGenovese | Apr 22 | Jun 3 | Aug 2 | 60 from transplant |
Tight means first harvest lands within two weeks of the median first fall frost. Statewide dates are the ZIP-weighted median of every NOAA 1991–2020 station Montana's ZIP codes resolve to; 37 of 369 ZIPs have no datable freeze and are left out.
Basil in Montana, city by city
Genovese Basil, scheduled from each city's nearest NOAA station — the same dates as its frost page.
| City | Last frost | Start indoors | Plant out | First harvest |
|---|---|---|---|---|
| Billingszone 5a | May 5 | Apr 7 | May 19 | Jul 18 |
| Missoulazone 5b | May 10 | Apr 12 | May 24 | Jul 23 |
| Great Fallszone 4b | May 6 | Apr 8 | May 20 | Jul 19 |
| Bozemanzone 5a | May 23 | Apr 25 | Jun 6 | Aug 5 |
What these basil become
What Montana basil need
Genovese Sweet Basil Seed
The large-leaf, low-anise Italian basil that pesto is defined by. Thai and lemon basils are good plants and wrong ingredients.
Organic Seed Starter Potting MixMust have
Seed-starting mix is not potting soil with a nicer label — it is finer, lighter, and low in nutrients on purpose, because a seedling's first roots want air and moisture, not fertiliser.
T8 Full-Spectrum Grow Lights, 1 ft 4-packMust have
A south window in March delivers a fraction of the light a pepper seedling needs, and the plant tells you by stretching. Two inches of LED above the canopy for 16 hours a day fixes it permanently.
5-Gallon Fabric Grow Bags, 5-Pack
Fabric pots air-prune roots and drain faster than a plastic pot can, which is the entire reason container tomatoes fail. Five gallons is the honest minimum for a pepper; a tomato wants ten.
Ocean Forest Potting SoilMust have
Pre-charged with enough nutrition to carry a transplant for its first month without feeding, which is exactly the window when most container plants stall.
6" Micro-Tip Pruning SnipsMust have
Ninety percent of sauce-garden cutting is snipping a pepper stem or a basil node, and a fine-tipped snip does it better than any pruner. Pulling peppers by hand tears the branch.
Mesh Strainers, Stainless, 3-Count
The last pass before bottling. A fine mesh catches the skin fragments and seed shards that make a hot sauce gritty and clog a woozy bottle's dripper insert.
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Basil in Montana: questions
When should I plant basil in Montana?
Transplant around Jun 3 at the statewide median; across the state that date runs from May 23 in the warmest tenth of Montana's ZIP codes to Jun 20 in the coldest. To cut the freeze risk to one year in ten, count from Jun 4 instead of the median last frost. Use the city table for your own town.
When do I start basil seeds indoors in Montana?
Around Apr 22 for Genovese Basil: 4 weeks before the statewide median last frost, on soil held at 70–80 °F.
When is the last frost in Montana?
The ZIP-weighted median of NOAA 1991–2020 station medians is May 20. In the warmest tenth of Montana's ZIP codes the median last frost falls on or before May 9; in the coldest tenth, on or after Jun 6.
When will Montana basil be ready to harvest?
Genovese Basil planted on the statewide date is ready around Aug 2: 60 days from transplant.
More for Montana
- When to plant tomatoes
- When to plant peppers
- When to plant tomatillos
- When to plant onions
- When to plant cilantro
- When to plant carrots
- When to plant mustard greens
Basil in every state → · Montana frost dates → · How frost-date math works →