One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant cardinal flower in Tempe can be figured out by using the USDA zone info.

Planting Calendar for Cardinal Flower

Frost tolerance for cardinal flower:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

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

The earliest that you can plant cardinal flower in Tempe 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 couple of weeks earlier by starting your cardinal flower indoors.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Tempe and it is different every year. Half of the time in Tempe it frosts late in the year after February 15 so be sure to be ready to cover your cardinal flower in the event of one of those late frosts.

USDA Zone Info for Tempe

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 Tempe

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