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

It's a good idea to figure out when it's the best time to plant primula by reviewing the USDA zone info for Cottage Grove.

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 one of those plants that can tolerate quite a bit of cold weather you can plant them earlier in the year than other plants that might not handle the cold.

The earliest that you can plant primula in Cottage Grove 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. If you wait any later than that and your primula may not have a chance to really do well. Starting your primula indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Cottage Grove. You can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Cottage Grove is not always accurate the actual date of last frost changes from year to year. Since half of the time in Cottage Grove last frost occurs after May 15 be ready to protect your primula if you have a late frost.

USDA Zone Info for Cottage Grove

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 Cottage Grove

You may be interested in your other planting guides for Cottage Grove.