One of the first steps you take when you are getting a good idea your gardening schedule is find your 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 torenia in Tucson should be estimated by looking at the USDA zone info.

Planting Calendar for Torenia

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

Torenia are not cold tolerant which means that it's important to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant torenia 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 torenia and expect a good harvest is probably September. If you wait any later than that and your torenia may not have a chance to grow to maturity. If you are starting your torenia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on February 15 in Tucson. It might get as low as 25°F during the coldest months of winter.

Always keep in mind that USDA zone info for Tucson is an average and the actual date of last frost will vary from year to year. Half of the time in Tucson you get a frost after February 15 so be sure to be ready to protect your torenia if you have a surprise late frost.

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.