The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Duluth can be used to estimate when it's possible to plant aurinia.

Planting Calendar for Aurinia

Frost tolerance for aurinia:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Aurinia are very cold tolerant which tells us that you can start planting them much earlier than more sensitive plants.

The earliest that you can plant aurinia 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 aurinia and expect a good harvest is probably August. Any later than that and your aurinia may not have a chance to really do well. If you are starting your aurinia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Duluth the average date of last frost happens on May 15. It might get as low as -30°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Duluth and it changes from year to year. Half of the time in Duluth you get surprised by a frost after May 15 so make sure that you are ready to protect your aurinia 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.