One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Duluth it's a good idea to estimate when it's a good idea to plant black eyed susans.

Planting Calendar for Black Eyed Susans

Frost tolerance for black eyed susans:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Black Eyed Susans do not do well in cold weather which tells us that you need to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant black eyed susans in Duluth is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant black eyed susans and expect a good harvest is probably August. You probably don't want to wait any later than that or else your black eyed susans may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your black eyed susans indoors.

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.

Keep in mind that USDA zone info for Duluth is an average and the actual date of last frost is different every year. Since half of the time in Duluth it frosts late in the year after May 15 be ready to cover your black eyed susans 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.