One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant calibrachoa in Tucson can be determined by reviewing the USDA zone info.

Planting Calendar for Calibrachoa

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

Since calibrachoa are one of those plants that can tolerate a tiny bit of cold weather you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant calibrachoa in Tucson 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 calibrachoa and expect a good harvest is probably September. If you wait any later than that and your calibrachoa may not have a chance to fully mature. You can get started a few weeks earlier by starting your calibrachoa indoors.

Last Frost Date

In Tucson 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.

Remember that USDA zone info for Tucson is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Tucson last frost occurs after February 15 be ready to cover your calibrachoa in the event of one of those late frosts.

USDA Zone Info for Tucson

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 Tucson

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