The USDA Zone info is a great tool for gardeners to help us figure out 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.

A common way of determining when it's possible to plant primroses is to check out the USDA zone info for Suisun City.

Planting Calendar for Primroses

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

Primroses are one of those plants that can tolerate quite a bit of cold weather which tells us that you can start planting them much earlier than more sensitive plants.

The earliest that you can plant primroses in Suisun City is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant primroses and expect a good harvest is probably October. If you wait any later than that and your primroses may not have a chance to fully mature. You can get started a little bit earlier by starting your primroses indoors.

Last Frost Date

In Suisun City the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Suisun City may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Suisun City it frosts late in the year after February 15 so make sure that you are ready to protect your primroses if you have one of those late frosts.

USDA Zone Info for Suisun City

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°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 30°F.

Plants to Grow in Suisun City

You may be interested in your other planting guides for Suisun City.