Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

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

Planting Calendar for Calliopsis

Frost tolerance for calliopsis:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since calliopsis are not cold tolerant it's necessary to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant calliopsis in Tucson 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 calliopsis and expect a good harvest is probably September. You probably don't want to wait any later than that or else your calliopsis may not have a chance to fully mature. Starting your calliopsis indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Tucson 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.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Tucson and it will vary from year to year. Since half of the time in Tucson last frost occurs after February 15 be ready to cover your calliopsis if you have 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.