When to plant Tomatoes in Keweenaw County, MI
Keweenaw County sits in cold Zone 5b. Plant Tomatoes May 26–June 16 for the single annual harvest; the October 1 first frost closes the window.
When to Plant Tomatoes in Keweenaw County, MI
Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.
Keweenaw County, Michigan is in USDA Zone 5b. The average last spring frost is May 19 and the first fall frost is October 1, giving you a growing season of approximately 135 days.
At an elevation of 1,035 feet, Keweenaw County receives approximately 40.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Tomatoes to ensure they mature before fall.
Keweenaw County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-6.9
Drainage
Well Drained
How Much Tomatoes to Grow
For a family of 4, plant approximately 12 tomatoes plants in about 24 sq ft. In Keweenaw County's 135-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Monthly Watering Guide for Tomatoes
Tomatoes needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Tomatoes Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.6" | 0" | ❄️ Dormant |
| Apr | — | 3.7" | 0" | ❄️ Dormant |
| May | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Jun | 4.3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Oct | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Keweenaw County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Tomatoes Planting Timeline — Keweenaw County, MI
Tomatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 24 | Mar 24 – Apr 7 |
| Transplant Outdoors | June 2 | Jun 2 – Jun 16 |
| Direct Sow | May 26 | May 26 – Jun 16 |
| Harvest | August 4 | Aug 4 – Oct 13 |
Plant 0.5" deep · 24" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
60–85 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
135 days in Keweenaw County
Growing Tips for Keweenaw County
Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.
Tomatoes in Other Locations
Frequently Asked Questions
When should I plant Tomatoes in Keweenaw County, MI?
Keweenaw County is in Zone 5b with an average last frost of May 19. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Keweenaw County, MI?
Keweenaw County, Michigan is in USDA Hardiness Zone 5b. The average last spring frost is May 19 and first fall frost is October 1.
When should I plant Tomatoes in Keweenaw County, MI?
In Keweenaw County, MI, plant Tomatoes after the last frost (around May 19) and before the first frost (around October 1). Best results when soil holds above 50°F.
What growing zone is Keweenaw County, MI for Tomatoes?
Keweenaw County sits in USDA Zone 5b. Tomatoes grows reliably in zones 3a through 11b, so it's a good fit here.
Can Tomatoes grow in Keweenaw County's climate?
Yes — Tomatoes grows well in Keweenaw County's temperate climate. Keweenaw County averages a 135-day frost-free season, with last frost around May 19 and first frost around October 1.
Your Keweenaw County Garden Planner — Free
A 22-page printable planner built for Keweenaw County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.