When to plant leeks in zone 4

Leeks in USDA zone 4

Average zone 4 frost dates: last spring frost ≈ May 10, first fall frost ≈ Sep 25 (138 frost-free days). Local dates can vary by 2-3 weeks.

Start indoors early; hill soil around stems for long white shanks.

When to plant leeks in zone 4?

Start seeds indoors: Mar 1 – Mar 15; Transplant outdoors: Apr 26 – May 17; Expected first harvest: from Aug 24.

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