AMSEED American Seed Intelligence Platform

Growing in Seattle

USDA zone (2023)
8b-9a
Median last frost
March 20
Median first frost
November 15
Growing season
~240 days

Frost dates are medians from NOAA climate normals: in half of years, frost comes later. The windows below are computed from each crop's planting rules against this city's dates, treat them as the center of the target, not the edges.

Tomato in Seattle

StepWindowNotes
Start seed indoorsJanuary 23 to February 6
Transplant outMarch 20 to April 10soil ≥ 60°F

Pepper in Seattle

StepWindowNotes
Start seed indoorsJanuary 9 to January 23
Transplant outMarch 27 to April 17soil ≥ 65°F

Other crops with rules for this climate

Data sources

Evidence: 2 sources, all independent references.

  1. USDA Plant Hardiness Zone Map (2023) · USDA Agricultural Research Service / Oregon State PRISM (2023), University or Government
  2. U.S. Climate Normals (1991-2020) · NOAA National Centers for Environmental Information (2021), University or Government