Growing sweet alyssum in zone 4b

(Zone 4b = an average winter low of -25°F to -20°F.)

In USDA zone 4b, the typical last spring frost is May 8 and the first fall frost is October 1. Here is when to plant sweet alyssum against those dates.

Start seeds indoorsMarch 27 to April 3

Transplant outdoorsMay 1 to May 8

Direct sow outdoorsApril 10 to April 24

These are zone 4b averages

Computed from 1,251 ZIP codes in zone 4b. Your town's frost dates vary; enter your ZIP for dates built on your nearest weather station.

Get my exact dates

USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service / Oregon State University PRISM Group. NOAA National Centers for Environmental Information, U.S. Climate Normals 1991-2020. Planting windows for sweet alyssum from NC State Extension (North Carolina Extension Gardener Plant Toolbox). Zone dates are medians; local conditions vary.