When to Plant Tomatoes in Montana
Montana spans USDA hardiness 3b to 6b (zones 3b to 6b on this page). Plant tomatoes by your local frost date, not the calendar — pick your zone below for exact start-indoors, transplant, and harvest dates.
Jump to: Zone 3b · Zone 4a · Zone 4b · Zone 5a · Zone 5b · Zone 6a · Zone 6b
Tomatoes planting calendar for Montana, Zone 3b
Average last spring frost
May 20
Average first fall frost
September 15
Start seeds indoors
Apr 8
Transplant outdoors
Jun 3
Projected first harvest
Aug 20
Most tomatoes mature in about 55 to 85 days depending on the variety. Full zone 3 guide (both 3a and 3b) →
Tomatoes planting calendar for Montana, Zone 4a
Average last spring frost
May 15
Average first fall frost
September 20
Start seeds indoors
Apr 3
Transplant outdoors
May 29
Projected first harvest
Aug 15
Most tomatoes mature in about 55 to 85 days depending on the variety. Full zone 4 guide (both 4a and 4b) →
Tomatoes planting calendar for Montana, Zone 4b
Average last spring frost
May 10
Average first fall frost
September 25
Start seeds indoors
Mar 29
Transplant outdoors
May 24
Projected first harvest
Aug 10
Most tomatoes mature in about 55 to 85 days depending on the variety. Full zone 4 guide (both 4a and 4b) →
Tomatoes planting calendar for Montana, Zone 5a
Average last spring frost
May 5
Average first fall frost
October 1
Start seeds indoors
Mar 24
Transplant outdoors
May 19
Projected first harvest
Aug 5
Most tomatoes mature in about 55 to 85 days depending on the variety. Full zone 5 guide (both 5a and 5b) →
Tomatoes planting calendar for Montana, Zone 5b
Average last spring frost
April 30
Average first fall frost
October 5
Start seeds indoors
Mar 19
Transplant outdoors
May 14
Projected first harvest
Jul 31
Most tomatoes mature in about 55 to 85 days depending on the variety. Full zone 5 guide (both 5a and 5b) →
Tomatoes planting calendar for Montana, Zone 6a
Average last spring frost
April 25
Average first fall frost
October 10
Start seeds indoors
Mar 14
Transplant outdoors
May 9
Projected first harvest
Jul 26
Most tomatoes mature in about 55 to 85 days depending on the variety. Full zone 6 guide (both 6a and 6b) →
Tomatoes planting calendar for Montana, Zone 6b
Average last spring frost
April 20
Average first fall frost
October 15
Start seeds indoors
Mar 9
Transplant outdoors
May 4
Projected first harvest
Jul 21
Most tomatoes mature in about 55 to 85 days depending on the variety. Full zone 6 guide (both 6a and 6b) →
Not sure which half-zone you're in? Set your ZIP in HomeSown for dates tuned to your exact location.
Varieties to grow
30 varieties of tomatoes in the HomeSown library. Tap any for its full grow guide.
Common problems with tomatoes
What to watch for, with identification and treatment for each
🌱 Grow tomatoes with a calendar built for your exact yard
HomeSown turns your ZIP code into a personalized planting calendar, watering reminders, and pest help. Free to start.
Start your free garden →