When to Plant Brussels sprouts

Enter your ZIP code to see the Brussels sprouts planting windows from the frost dates at the nearest weather station. The rules below come from university extension publications and count from the average last or first frost.

Your area

Risk level

How much frost risk you'll accept. Each level uses the frost dates with this chance of a frost after the last-frost date or before the first-frost date: Conservative 10%, Typical 30%, Aggressive 50%.

Planting year

The year the frost dates and windows are placed on.

Brussels sprouts planting windows

Brussels sprouts planting rules

Each rule counts days or weeks from the average last spring frost or first fall frost in its source. YepPlant applies the same count to the 32°F frost dates at each risk level: Conservative (10%), Typical (30%), and Aggressive (50%). A range in a rule becomes a range in the window. Where sources differ or don't give a single value, the value is YepPlant's reading of the sources, and it stays within what they say.

Brussels sprouts planting rules, from university extension publications
Rule	Value	Sources
Frost threshold	32°F frost dates	—
Transplant outdoors	28 to 14 days before the last spring frost	UNHYepPlant's reading of these sources
Start seeds indoors	4 to 7 weeks before transplanting	NCSU, CLEM, UNHYepPlant's reading of these sources
Bought seedlings	Transplant dates apply only to seedlings you start indoors	NCSU, UNH, UMD-BSYepPlant's reading of these sources
Sow outdoors	Not available	—
Days to maturity from transplanting	40 to 100 days	UMD-P, UMD-BS, PUR, NCSUYepPlant's reading of these sources
Frost Tender Factor	None: not added for this crop	UNL
Last transplant date	First fall frost − days to maturity from transplanting	—
Last indoor sowing date	Last transplant date − weeks to start seeds indoors	UNLYepPlant's reading of these sources
Fall planting	Transplant from 14 days before the earliest last transplant date through the latest last transplant date. Fall seedlings are started indoors the same number of weeks before transplanting as in spring	PUR, NCSU, UNLYepPlant's reading of these sources
Crop rotation	Plant this crop's family in the same spot at most once every 3 years	NCSU

Not available means no rule from the sources is used for it, so no window depends on it. Rows without a source follow the rules shared by all crops, described on the methods and sources page.

Sources

University extension publications, with the date each was retrieved. The frost dates come from NOAA's 1991–2020 Climate Normals at the weather station nearest your ZIP code, and the station is found from the Census Bureau's ZIP Code Tabulation Areas.

UNH: UNH Cooperative Extension: Growing Vegetables: When to Plant your Vegetable Garden: Used for: Transplant outdoors, Start seeds indoors, Bought seedlings. Retrieved October 13, 2026.
CSU: Colorado State University Extension, GardenNotes #720: Vegetable Planting Guide: Consulted, but no rule on this page comes from it. Retrieved October 13, 2026.
USU: Utah State University Extension: Suggested Vegetable Planting Dates for Utah: Consulted, but no rule on this page comes from it. Retrieved October 13, 2026.
UMD-P: University of Maryland Extension: Vegetables for Spring and Fall Planting: Used for: Days to maturity from transplanting. Retrieved October 13, 2026.
NCSU: NC State Extension, Extension Gardener Handbook Chapter 16: Vegetable Gardening: Used for: Start seeds indoors, Bought seedlings, Days to maturity from transplanting, Fall planting, Crop rotation. Retrieved October 13, 2026.
CLEM: Clemson Cooperative Extension, HGIC 1259: Starting Seeds Indoors: Used for: Start seeds indoors. Retrieved October 13, 2026.
PUR: Purdue Extension, HO-66-W: The Fall Vegetable Garden: Used for: Days to maturity from transplanting, Fall planting. Retrieved October 13, 2026.
UNL: Nebraska Extension, NebGuide G1343: Fall Vegetable Gardening: Used for: Frost Tender Factor, Last indoor sowing date, Fall planting. Retrieved October 13, 2026.
OSU: Oregon State University Extension: Plant cold-hardy vegetables now for a spring harvest: Consulted, but no rule on this page comes from it. Retrieved October 13, 2026.
UMD-BS: University of Maryland Extension HGIC: Growing Brussels Sprouts in a Home Garden: Used for: Bought seedlings, Days to maturity from transplanting. Retrieved October 13, 2026.

Data sources

NOAA U.S. Climate Normals, frost dates, 1991–2020 normals, version 1.0.1: Files: us-climate-normals_1991-2020_v1.0.1_annualseasonal_multivariate_by-station_c20230404.tar.gz, inventory_30yr.txt from NOAA NCEI. Retrieved October 10, 2026.
U.S. Census Bureau ZIP Code Tabulation Areas, 2026 Gazetteer Files and 2020 ZCTA to County Relationship File: Files: 2026_Gaz_zcta_national.zip, tab20_zcta520_county20_natl.txt, national_state2020.txt from the U.S. Census Bureau. Retrieved October 10, 2026.