When to Plant Marshmallow in Montana
Montana spans USDA hardiness 3b to 6b (zones 3b to 6b on this page). Plant marshmallow 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
Marshmallow planting calendar for Montana, Zone 3b
Average last spring frost
May 20
Average first fall frost
September 15
Start seeds indoors
Mar 25
Transplant outdoors
Jun 3
Projected first harvest
Oct 1
Marshmallow is ready to harvest in about 120 days. Full zone 3 guide (both 3a and 3b) →
Marshmallow planting calendar for Montana, Zone 4a
Average last spring frost
May 15
Average first fall frost
September 20
Start seeds indoors
Mar 20
Transplant outdoors
May 29
Projected first harvest
Sep 26
Marshmallow is ready to harvest in about 120 days. Full zone 4 guide (both 4a and 4b) →
Marshmallow planting calendar for Montana, Zone 4b
Average last spring frost
May 10
Average first fall frost
September 25
Start seeds indoors
Mar 15
Transplant outdoors
May 24
Projected first harvest
Sep 21
Marshmallow is ready to harvest in about 120 days. Full zone 4 guide (both 4a and 4b) →
Marshmallow planting calendar for Montana, Zone 5a
Average last spring frost
May 5
Average first fall frost
October 1
Start seeds indoors
Mar 10
Transplant outdoors
May 19
Projected first harvest
Sep 16
Marshmallow is ready to harvest in about 120 days. Full zone 5 guide (both 5a and 5b) →
Marshmallow planting calendar for Montana, Zone 5b
Average last spring frost
April 30
Average first fall frost
October 5
Start seeds indoors
Mar 5
Transplant outdoors
May 14
Projected first harvest
Sep 11
Marshmallow is ready to harvest in about 120 days. Full zone 5 guide (both 5a and 5b) →
Marshmallow planting calendar for Montana, Zone 6a
Average last spring frost
April 25
Average first fall frost
October 10
Start seeds indoors
Feb 28
Transplant outdoors
May 9
Projected first harvest
Sep 6
Marshmallow is ready to harvest in about 120 days. Full zone 6 guide (both 6a and 6b) →
Marshmallow planting calendar for Montana, Zone 6b
Average last spring frost
April 20
Average first fall frost
October 15
Start seeds indoors
Feb 23
Transplant outdoors
May 4
Projected first harvest
Sep 1
Marshmallow is ready to harvest in about 120 days. 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
1 variety of marshmallow in the HomeSown library. Tap any for its full grow guide.
Common problems with marshmallow
What to watch for, with identification and treatment for each
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