One of the best tools that you have as gardeners to help us figure out 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.

In Eureka you can figure out when it's possible to plant primroses by referring to the USDA zone info.

Planting Calendar for Primroses

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

Since primroses do well in cold you can plant them quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant primroses in Eureka 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 fully mature. Starting your primroses indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Eureka. You should expect an average low temperature of -15°F in the coldest months of winter.

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

USDA Zone Info for Eureka

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Eureka

You may be interested in your other planting guides for Eureka.