When to Plant Milk Thistle in Zone 4
In USDA zone 4, plant outdoors May 29 to October 26, and expect your first harvest around October 26.
Milk Thistle planting calendar for USDA Zone 4
Direct sow
May 29
Projected first harvest
Oct 26
Milk Thistle is ready to harvest in about 150 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 milk thistle
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 milk thistle need about 150 days to mature.
Varieties to grow
1 variety of milk thistle in the HomeSown library. Tap any for its full grow guide.
Common problems with milk thistle
What to watch for, with identification and treatment for each
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