Frost Dates for Stevensville, MT 59870
Last spring frost May 29 · First fall frost September 16 · 110 frost-free days · USDA Zone 5b
ZIP 59870 has about 12,500 people.
Short season: 110 frost-free days. Spring frost risk spans May 12–June 15 (34 days). Fall frost risk spans September 2–September 30 (28 days).
Frost probability for 59870
| Frost | 10% | 50% | 90% |
|---|---|---|---|
| Spring (last frost) | June 15 | May 29 | May 12 |
| Fall (first frost) | September 2 | September 16 | September 30 |
Dates come from NOAA 1971–2000 freeze probabilities at WESTERN AG RSCH CTR (20.9 km away); the 50% date is the median year.
Which crops fit a 110-day season in Stevensville
In Stevensville (110 frost-free days, a short season), 30 of 56 planner crops fit outright, 15 get two plantings, 8 need an indoor start, 2 don't reliably mature, 1 crop is perennial.
| Crop | Start indoors | Plant out / sow | Days you have | Verdict | Last sow date |
|---|---|---|---|---|---|
| Tomato | Apr 24 | Jun 12–Jun 19 | 68 | head-start: Even planted out Jun 12, the outdoor season is about 12 days short; choose an early variety or grow under cover. | — |
| Pepper | Apr 17 | Jun 12–Jun 19 | 68 | head-start: Even planted out Jun 12, the outdoor season is about 7 days short; choose an early variety or grow under cover. | — |
| Lettuce | Apr 3 | May 1–May 8 | 145 | two-plantings: Plant May 1 and again by Jul 26; both mature before Sep 23. | Jul 26 |
| Carrots | — | May 8–May 15 | 152 | fits: 70 days to maturity, 152 available after May 8. | Jul 15 |
| Cucumber | May 8 | Jun 12–Jun 19 | 82 | fits: 60 days to maturity, 82 available after Jun 12. | Jun 20 |
| Beans | — | Jun 5–Jun 19 | 96 | fits: 60 days to maturity, 96 available after Jun 5. | Jun 27 |
| Peas | — | Apr 3–Jun 12 | 173 | fits: 65 days to maturity, 173 available after Apr 3. | Jul 6 |
| Zucchini | May 15 | Jun 12–Jun 19 | 82 | fits: 55 days to maturity, 82 available after Jun 12. | Jun 25 |
| Onion | Mar 6 | May 1–May 15 | 145 | fits: 100 days to maturity, 145 available after May 1. | — |
| Spinach | — | Apr 3–May 22 | 187 | two-plantings: Plant Apr 3 and again by Aug 14; both mature before Oct 7. | Aug 14 |
| Kale | Mar 20 | May 1–May 15 | 159 | two-plantings: Plant May 1 and again by Jul 30; both mature before Oct 7. | Jul 30 |
| Broccoli | Apr 3 | May 1–May 15 | 145 | fits: 80 days to maturity, 145 available after May 1. | Jun 21 |
| Cabbage | Apr 3 | May 1–May 15 | 159 | fits: 70 days to maturity, 159 available after May 1. | Jul 15 |
| Radish | — | Apr 3–Jun 26 | 173 | two-plantings: Plant Apr 3 and again by Aug 15; both mature before Sep 23. | Aug 15 |
| Beets | — | Apr 3–Jun 26 | 173 | two-plantings: Plant Apr 3 and again by Jul 16; both mature before Sep 23. | Jul 16 |
| Potatoes | — | May 15–May 22 | 131 | fits: 90 days to maturity, 131 available after May 15. | — |
| Garlic | — | Sep 16 | 215 | overwinter: Plant Sep 16 to Oct 7; harvest the following summer. | Oct 7 |
| Strawberry | — | Apr 24–Jun 19 | 166 | perennial: A perennial: plant Apr 24; it fruits from the following year and keeps producing for several years. | — |
| Corn | May 1 | Jun 5–Jun 12 | 82 | fits: 75 days to maturity, 82 available after Jun 5. | — |
| Pumpkin | May 15 | Jun 12–Jun 12 | 75 | no-fit: Needs 100 days; Stevensville has 75 after Jun 12. | — |
| Cauliflower | Apr 17 | May 22–Jun 5 | 124 | fits: 75 days to maturity, 124 available after May 22. | Jun 26 |
| Swiss Chard | Apr 3 | May 15–May 15 | 131 | two-plantings: Plant May 15 and again by Jul 16; both mature before Sep 23. | Jul 16 |
| Arugula | — | Apr 3–Jun 26 | 187 | two-plantings: Plant Apr 3 and again by Aug 14; both mature before Oct 7. | Aug 14 |
| Brussel Sprouts | Apr 3 | May 1–May 15 | 159 | fits: 100 days to maturity, 159 available after May 1. | Jun 15 |
| Butternut Squash | May 15 | Jun 12–Jun 19 | 75 | no-fit: Needs 100 days; Stevensville has 75 after Jun 12. | — |
| Eggplant | Apr 10 | Jun 12–Jun 19 | 68 | head-start: Even planted out Jun 12, the outdoor season is about 2 days short; choose an early variety or grow under cover. | — |
| Okra | May 1 | Jun 5–Jun 12 | 89 | fits: 55 days to maturity, 89 available after Jun 5. | Jun 25 |
| Basil | Apr 24 | Jun 19–Jun 19 | 75 | fits: 60 days to maturity, 75 available after Jun 19. | Jun 20 |
| Cilantro | — | May 1–May 22 | 145 | two-plantings: Plant May 1 and again by Jul 21; both mature before Sep 23. | Jul 21 |
| Parsley | Mar 20 | Jun 5–Jun 12 | 110 | fits: 70 days to maturity, 110 available after Jun 5. | Jul 1 |
| Celery | Mar 20 | Jun 5–Jun 19 | 110 | head-start: Even planted out Jun 5, the outdoor season is about 10 days short; choose an early variety or grow under cover. | — |
| Scallions | Mar 20 | May 1–May 15 | 159 | two-plantings: Plant May 1 and again by Jul 25; both mature before Oct 7. | Jul 25 |
| Turnip | — | May 1–May 15 | 159 | two-plantings: Plant May 1 and again by Aug 4; both mature before Oct 7. | Aug 4 |
| Kohlrabi | — | Apr 17–May 1 | 173 | two-plantings: Plant Apr 17 and again by Jul 30; both mature before Oct 7. | Jul 30 |
| Bok Choy | May 1 | May 22–May 29 | 124 | two-plantings: Plant May 22 and again by Jul 26; both mature before Sep 23. | Jul 26 |
| Collards | Mar 20 | May 1–May 15 | 159 | two-plantings: Plant May 1 and again by Jul 25; both mature before Oct 7. | Jul 25 |
| Cantaloupe | May 15 | Jun 12–Jun 19 | 68 | head-start: Even planted out Jun 12, the outdoor season is about 17 days short; choose an early variety or grow under cover. | — |
| Chives | Mar 6 | Jun 5–Jun 12 | 124 | fits: 90 days to maturity, 124 available after Jun 5. | — |
| Dill | — | Apr 3–Jun 26 | 173 | two-plantings: Plant Apr 3 and again by Jul 16; both mature before Sep 23. | Jul 16 |
| Oregano | Mar 20 | Jun 5–Jun 12 | 124 | fits: 80 days to maturity, 124 available after Jun 5. | — |
| Rosemary | Mar 6 | Jun 5–Jun 12 | 110 | fits: 80 days to maturity, 110 available after Jun 5. | — |
| Sage | Apr 3 | Jun 5–Jun 12 | 124 | fits: 75 days to maturity, 124 available after Jun 5. | — |
| Thyme | Mar 20 | Jun 5–Jun 12 | 124 | fits: 90 days to maturity, 124 available after Jun 5. | — |
| Calendula | Apr 17 | May 15–May 29 | 131 | two-plantings: Plant May 15 and again by Jul 21; both mature before Sep 23. | Jul 21 |
| Cosmos | May 1 | May 29–Jun 12 | 96 | fits: 60 days to maturity, 96 available after May 29. | Jun 20 |
| Lavender | Mar 6 | May 29–Jun 12 | 131 | fits: 90 days to maturity, 131 available after May 29. | — |
| Marigolds | Apr 17 | May 29–Jun 5 | 96 | fits: 50 days to maturity, 96 available after May 29. | Jun 30 |
| Melons | May 15 | Jun 12–Jun 19 | 68 | head-start: Even planted out Jun 12, the outdoor season is about 17 days short; choose an early variety or grow under cover. | — |
| Mint | — | May 29–Jun 12 | 131 | fits: 90 days to maturity, 131 available after May 29. | — |
| Nasturtiums | May 1 | May 29–Jun 5 | 96 | fits: 55 days to maturity, 96 available after May 29. | Jun 25 |
| Pole Beans | — | Jun 5–Jun 19 | 89 | fits: 65 days to maturity, 89 available after Jun 5. | Jun 15 |
| Spaghetti Squash | May 15 | Jun 12–Jun 19 | 75 | head-start: Even planted out Jun 12, the outdoor season is about 15 days short; choose an early variety or grow under cover. | — |
| Sunflowers | — | May 29–Jun 12 | 96 | fits: 70 days to maturity, 96 available after May 29. | Jun 10 |
| Tomatillos | Apr 3 | Jun 5–Jun 12 | 75 | fits: 75 days to maturity, 75 available after Jun 5. | — |
| Watermelon | May 15 | Jun 5–Jun 12 | 75 | head-start: Even planted out Jun 5, the outdoor season is about 5 days short; choose an early variety or grow under cover. | — |
| Yellow Squash | May 15 | Jun 12–Jun 19 | 82 | fits: 55 days to maturity, 82 available after Jun 12. | Jun 25 |
| Zinnias | May 1 | May 29–Jun 12 | 96 | fits: 60 days to maturity, 96 available after May 29. | Jun 20 |
Month by month in Stevensville
| Month | What to do |
|---|---|
| January | Plan your garden layout and order seeds. Research varieties suited to your frost dates. |
| February | Start the slowest-growing crops indoors: onions, leeks, and celery (10–12 weeks before last frost). |
| March | Start indoors: Chives (Mar 6), Lavender (Mar 6), Onion (Mar 6), Rosemary (Mar 6), Celery (Mar 20), Collards (Mar 20), +5 more. |
| April | Start indoors: Broccoli (Apr 3), Brussel Sprouts (Apr 3), Cabbage (Apr 3), Lettuce (Apr 3), Sage (Apr 3), Swiss Chard (Apr 3), +8 more. Direct sow from: Arugula (Apr 3), Beets (Apr 3), Dill (Apr 3), Peas (Apr 3), Radish (Apr 3), Spinach (Apr 3), +1 more. Plant: Strawberry (Apr 24). |
| May | Start indoors: Bok Choy (May 1), Corn (May 1), Cosmos (May 1), Nasturtiums (May 1), Okra (May 1), Zinnias (May 1), +9 more. Direct sow from: Cilantro (May 1), Turnip (May 1), Carrots (May 8), Potatoes (May 15), Sunflowers (May 29). Transplant from: Broccoli (May 1), Brussel Sprouts (May 1), Cabbage (May 1), Collards (May 1), Kale (May 1), Lettuce (May 1), +12 more. Last frost around May 29. |
| June | Direct sow from: Beans (Jun 5), Pole Beans (Jun 5). Transplant from: Celery (Jun 5), Chives (Jun 5), Corn (Jun 5), Okra (Jun 5), Oregano (Jun 5), Parsley (Jun 5), +17 more. Last sowing dates: Sunflowers (Jun 10), Brussel Sprouts (Jun 15), Pole Beans (Jun 15), Basil (Jun 20), Cosmos (Jun 20), Cucumber (Jun 20), +9 more. |
| July | Last sowing dates: Parsley (Jul 1), Peas (Jul 6), Cabbage (Jul 15), Carrots (Jul 15), Beets (Jul 16), Dill (Jul 16), +9 more. |
| August | Last sowing dates: Turnip (Aug 4), Arugula (Aug 14), Spinach (Aug 14), Radish (Aug 15). |
| September | Direct sow from: Garlic (Sep 16). First frost around September 16. |
| October | Last sowing dates: Garlic (Oct 7). |
| November | Clean up spent plants. Add compost to beds. Rest, review, and plan next year's garden. |
| December | Clean up spent plants. Add compost to beds. Rest, review, and plan next year's garden. |
Frequently Asked Questions
What is the last frost date for Stevensville, MT (ZIP 59870)?
The median last spring frost date for Stevensville, MT (ZIP code 59870) is around May 29. This is the 50th-percentile date — meaning half of all years see frost end before this date. Use the 10% and 90% dates to understand the full range of risk in your area. One year in ten frost ends before May 12; one in ten it runs past June 15.
What is the first fall frost date in Stevensville, MT?
The median first fall frost date for Stevensville, MT is around September 16. Plan to harvest or protect frost-sensitive crops like tomatoes and peppers at least a week before this date to avoid losses. The first frost arrives around September 2 in the earliest one-in-ten years, so cover tomatoes and peppers from then.
How long is the growing season in Stevensville, MT?
The frost-free growing season in Stevensville is about 110 days. This window — from your last spring frost to your first fall frost — is when warm-season vegetables thrive. Cold-hardy crops like kale, spinach, and peas can extend your season by weeks on either side. In Stevensville (110 frost-free days, a short season), 30 of 56 planner crops fit outright, 15 get two plantings, 8 need an indoor start, 2 don't reliably mature, 1 crop is perennial.
What USDA hardiness zone is Stevensville, MT?
Stevensville, MT is in USDA hardiness zone 5b (2023 USDA Plant Hardiness Zone Map). Zones come from the average coldest winter temperature, so they tell you which perennials survive the winter; the frost dates on this page tell you when to plant.
When should I start tomatoes indoors in Stevensville, MT?
Start tomatoes indoors Apr 24 and plant out Jun 12 in Stevensville. The planner uses the local median last frost and this crop's indoor-start and transplant offsets.
How many plantings of lettuce fit in Stevensville?
Two: plant May 1 and again by Jul 26; both mature before Sep 23.
When do I plant garlic in Stevensville?
Sep 16 to Oct 7; it overwinters and is ready the following summer.
Can I grow Celery in Stevensville?
Yes, with help. Even planted out Jun 5, the outdoor season is about 10 days short; choose an early variety or grow under cover.
Which nearby ZIP has a longer season?
Missoula (ZIP 59808) has 119 frost-free days, 9 more than Stevensville (ZIP 59870). See Missoula ZIP 59808 frost dates
Nearby and related
- Frost dates for Missoula, MT 59801 (23.5 mi)
- Frost dates for Hamilton, MT 59840 (23.6 mi)
- Frost dates for Missoula, MT 59808 (32 mi)
- Frost dates for Polson, MT 59860 (82.8 mi)
- Frost dates for Butte, MT 59701 (82.9 mi)
- When to plant in MT
- When to plant Beans in MT
- When to plant Strawberries in MT
- When to plant Beets in MT
- When to plant Broccoli in MT
- When to plant Carrots in MT
- When to plant Kale in MT
- Look up another ZIP