Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant broccoli in Duluth can be estimated by looking at the USDA zone info.

Planting Calendar for Broccoli

Frost tolerance for broccoli:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Broccoli are moderately cold tolerant which tells us that you can get them planted earlier than other frost tender plants.

The earliest that you can plant broccoli in Duluth is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant broccoli and expect a good harvest is probably August. You probably don't want to wait any later than that or else your broccoli may not have a chance to really do well. If you are starting your broccoli indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Duluth. In the coldest months of winter you should expect an average low temperature of -30°F.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Duluth and it is different every year. Half of the time in Duluth there is a last frost after May 15 so make sure that you are prepared to cover your broccoli in the event of a late frost.

USDA Zone Info for Duluth

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Duluth

You may be interested in your other planting guides for Duluth.