Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Circle Pines you should be able to figure out when it's the best time to plant primula.

Planting Calendar for Primula

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

Since primula are very cold tolerant you can plant them much earlier in the year than other frost tender plants.

The earliest that you can plant primula in Circle Pines 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 primula and expect a good harvest is probably August. You probably don't want to wait any later than that or else your primula may not have a chance to really do well. Starting your primula indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Circle Pines the average date of last frost happens on May 15. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Circle Pines is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Circle Pines you get surprised by a frost after May 15 so make sure that you are prepared to cover your primula in the event of one of those late frosts.

USDA Zone Info for Circle Pines

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Circle Pines

You may be interested in your other planting guides for Circle Pines.