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.

It's possible to estimate when it's possible to plant primroses by referring to the USDA zone info for Spirit Lake.

Planting Calendar for Primroses

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

Primroses do ok in a bit of cold which means that you can plant them earlier in the year than other plants that might not handle the cold.

The earliest that you can plant primroses in Spirit Lake is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant primroses and expect a good harvest is probably September. If you wait any later than that and your primroses may not have a chance to really do well. If you are starting your primroses 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 April 15 in Spirit Lake. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Spirit Lake is an average the actual date of last frost changes from year to year. Half of the time in Spirit Lake you get surprised by a frost after April 15 so make sure that you are ready to protect your primroses in the event of a late frost.

USDA Zone Info for Spirit Lake

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Spirit Lake

You may be interested in your other planting guides for Spirit Lake.