When to Plant Rosemary in Zone 4
In USDA zone 4, start seeds indoors around March 6, transplant or plant outdoors May 29 to August 27, and expect your first harvest around August 27.
Rosemary planting calendar for USDA Zone 4
Start seeds indoors
Mar 6
Transplant outdoors
May 29
Projected first harvest
Aug 27
Most rosemary mature in about 90 days. Dates use USDA zone 4a average frost dates. Set your ZIP in HomeSown for dates tuned to your exact location.
What zone 4 means for rosemary
Average last spring frost
May 15
Average first fall frost
September 20
Those two dates are what set the schedule above. Zone 4 gives you roughly 128 frost-free days, and rosemary need about 90 days to mature.
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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