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

The first chance to plant cardinal flower in San Bernardino can be figured out by checking out the USDA zone info.

Planting Calendar for Cardinal Flower

Frost tolerance for cardinal flower:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's probably not a good idea to plant cardinal flower until after the last frost has passed because they require warm weather.

The earliest that you can plant cardinal flower in San Bernardino is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant cardinal flower and expect a good harvest is probably September. Any later than that and your cardinal flower may not have a chance to fully mature. Starting your cardinal flower indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in San Bernardino. In the coldest months of winter you should expect an average low temperature of 25°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for San Bernardino and it changes from year to year. Half of the time in San Bernardino you get surprised by a frost after February 15 so make sure that you are prepared to protect your cardinal flower in the event of a surprise 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.