Broccoli transplants go out two to four weeks before your last spring frost, and again in late summer for fall, which is often the better crop. Find your zone below, or enter your ZIP code for dates based on the weather station closest to you.
Broccoli dates for your ZIP code
Planting times based on university extension guidance (UNH, Cornell, Purdue, Minnesota, Nebraska and UMass Extension). Frost dates from NOAA 1991–2020 U.S. Climate Normals, nearest weather station. Zones derived from the 2023 USDA Plant Hardiness Zone Map data (PRISM Climate Group, Oregon State University). This is not the official USDA Plant Hardiness Zone Map.
Broccoli planting dates by zone
| USDA zone | When to plant |
|---|---|
| Zone 3 | April 25 – May 9 |
| Zone 4 | April 18 – May 2 |
| Zone 5 | April 10 – April 24 |
| Zone 6 | April 3 – April 17 |
| Zone 7 | March 20 – April 3 |
| Zone 8 | March 3 – March 17 |
| Zone 9 | February 3 – February 17 |
Not sure of your zone? Look it up by ZIP code.
Why broccoli is planted before the last frost
Broccoli is a cool-season crop. It tolerates light frost and forms its best heads in mild weather. In heat, heads loosen and the yellow flowers open early. That is why transplants go out two to four weeks before the last spring frost, and why broccoli is grown again in late summer for a fall harvest.
How to plant broccoli
- Start seeds indoors four to six weeks before transplanting, ¼–½ inch deep.
- Transplant young, vigorous plants. Avoid plants that are overgrown or dried out in their pots.
- Space plants 16–24 inches apart in rows 24–36 inches apart.
- Use a starter fertilizer at planting, then side-dress three weeks later.
- Keep the soil evenly moist. Severe drought causes small heads.
Harvesting broccoli
Cut the main head when it is 4–6 inches across and the buds are tight and green, before any yellow flowers appear. Leave 5–6 inches of stem. Side shoots then grow from the leaf joints and give you smaller heads for several weeks. Most heading broccoli is ready 55–65 days after transplanting.
Frequently asked questions
Can broccoli handle frost?
Yes, light frost. Broccoli is a cool-season crop set out two to four weeks before your last spring frost. Long cold spells on young plants can cause small heads.
Does broccoli grow back after cutting?
Yes. After you cut the main head, side shoots grow from the leaf joints and produce smaller heads for several weeks.
Why is my broccoli flowering?
Heat. Broccoli that heads in hot weather opens its yellow flowers fast. Harvest promptly, and plant earlier in spring or grow a fall crop.
Sources. Planting dates use the median frost dates of each USDA zone, calculated from NOAA climate data for every ZIP code in the zone.