The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Prior Lake should be used to estimate 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.

You can plant primula much earlier in the year because they do well in cold.

The earliest that you can plant primula in Prior Lake 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. Any later than that and your primula may not have a chance to fully mature. If you are starting your primula indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Prior Lake. It might get as low as -25°F during the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Prior Lake and it is different every year. Half of the time in Prior Lake last frost occurs after May 15 so make sure that you are prepared to protect your primula in the event of one of those late frosts.

USDA Zone Info for Prior Lake

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 Prior Lake

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