One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. 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 Sun Prairie should be reviewed to determine when it's possible to plant primroses.

Planting Calendar for Primroses

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

Primroses do well in cold which means that you can get them planted much earlier than other plants that might not handle the cold.

The earliest that you can plant primroses in Sun Prairie 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. You probably don't want to wait any later than that or else your primroses may not have a chance to fully mature. 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 Sun Prairie. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Sun Prairie may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Sun Prairie it frosts late in the year after April 15 be ready to cover your primroses in the event of a surprise late frost.

USDA Zone Info for Sun Prairie

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 Sun Prairie

You may be interested in your other planting guides for Sun Prairie.