The USDA Zone info is a great tool for gardeners to help us figure out your gardening 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 Phoenix should be used to determine when you can plant bidens.

Planting Calendar for Bidens

Frost tolerance for bidens:	Not tolerant of frost.
When to plant:	After the last frost.

It's probably a bad idea to plant bidens until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant bidens in Phoenix is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant bidens and expect a good harvest is probably August. If you wait any later than that and your bidens may not have a chance to really do well. If you are starting your bidens indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Phoenix the average date of last frost happens on March 15. You should expect an average low temperature of 10°F in the coldest months of winter.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Phoenix and it changes from year to year. Half of the time in Phoenix there is a last frost after March 15 so always be ready to cover your bidens in the event of a surprise late frost.

USDA Zone Info for Phoenix

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Phoenix

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