One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for San Bernardino you should be able to estimate when you can plant missouri primrose.

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 earlier in the year because they do well in moderate cold.

The earliest that you can plant missouri primrose in San Bernardino 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. Any later than that and your missouri primrose may not have a chance to really do well. Starting your missouri primrose indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in San Bernardino. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for San Bernardino is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in San Bernardino it frosts late in the year after February 15 so always be ready to cover your missouri primrose in the event of a late frost.

USDA Zone Info for San Bernardino

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 San Bernardino

You may be interested in your other planting guides for San Bernardino.