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When to Plant St. John's Wort in Zone 4

In USDA zone 4, start seeds indoors around March 20, transplant or plant outdoors May 29 to September 26, and expect your first harvest around September 26.

St. John's Wort planting calendar for USDA Zone 4

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Start seeds indoors

Mar 20

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Transplant outdoors

May 29

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Projected first harvest

Sep 26

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🌱 Start indoors🌿 Growing outside🌾 HarvestTodayZone 4a — approximate

St. John's Wort is ready to harvest in about 120 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 st. john's wort

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 st. john's wort need about 120 days to mature.

Varieties to grow

1 variety of st. john's wort in the HomeSown library. Tap any for its full grow guide.

Common problems with st. john's wort

What to watch for, with identification and treatment for each

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