The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant cardinal flower in San Diego should 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 has passed.

Cardinal Flower require warm weather which means that you need to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant cardinal flower in San Diego 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 grow to maturity. You can get started a few weeks earlier by starting your cardinal flower indoors.

Last Frost Date

In San Diego the average date of last frost happens on February 15. You should expect an average low temperature of 20°F in the coldest months of winter.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for San Diego and it will vary from year to year. Since half of the time in San Diego it frosts late in the year after February 15 be ready to cover your cardinal flower if you have a late frost.

USDA Zone Info for San Diego

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in San Diego

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