When to Plant Rosemary in Zone 3
In USDA zone 3a, start seeds indoors around March 21, transplant or plant outdoors June 13 to September 11, and expect your first harvest around September 11. (3a shown here — see 3a and 3b dates separately below.)
Rosemary planting calendar for USDA Zone 3a
Average last spring frost
May 30
Average first fall frost
September 10
Start seeds indoors
Mar 21
Transplant outdoors
Jun 13
Projected first harvest
Sep 11
Most rosemary mature in about 90 days, needing roughly 103 frost-free days in zone 3a.
Rosemary planting calendar for USDA Zone 3b
Average last spring frost
May 20
Average first fall frost
September 15
Start seeds indoors
Mar 11
Transplant outdoors
Jun 3
Projected first harvest
Sep 1
Most rosemary mature in about 90 days, needing roughly 118 frost-free days in zone 3b.
Not sure whether you're in 3a or 3b? Set your ZIP in HomeSown for dates tuned to your exact location.
Varieties to grow
2 varieties of rosemary in the HomeSown library. Tap any for its full grow guide.
Common problems with rosemary
What to watch for, with identification and treatment for each
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