Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for San Bernardino can be read to determine when to plant flower-of-an-hour.

Planting Calendar for Flower-of-an-Hour

Frost tolerance for flower-of-an-hour:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Flower-of-an-Hour do ok in some cold which means that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant flower-of-an-hour in San Bernardino 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 flower-of-an-hour and expect a good harvest is probably September. If you wait any later than that and your flower-of-an-hour may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your flower-of-an-hour indoors.

Last Frost Date

In San Bernardino the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 25°F.

Keep in mind that USDA zone info for San Bernardino is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in San Bernardino there is a last frost after February 15 so make sure that you are ready to protect your flower-of-an-hour if you have 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.