Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant missouri primrose in Napa can be determined by referring to the USDA zone info.

Planting Calendar for Missouri Primrose

Frost tolerance for missouri primrose:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant missouri primrose a little bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant missouri primrose in Napa 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 missouri primrose and expect a good harvest is probably October. If you wait any later than that and your missouri primrose may not have a chance to grow to maturity. Starting your missouri primrose indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Napa. In the coldest months of winter you can expect an average low temperature of 25°F.

It's important to remember that USDA zone info for Napa is not always accurate and the actual date of last frost changes from year to year. Half of the time in Napa it frosts late in the year after February 15 so always be ready to protect your missouri primrose if you have a late frost.

USDA Zone Info for Napa

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 Napa

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