The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of estimating when it's the best time to plant torenia is to use the USDA zone info for Roma.

Planting Calendar for Torenia

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

Since torenia do not do well in cold weather it's necessary to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant torenia in Roma 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 fully mature. Starting your torenia indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Roma the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Roma and it changes from year to year. Half of the time in Roma you get a frost after February 15 so make sure that you are ready to protect your torenia in the event of a late frost.

USDA Zone Info for Roma

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 Roma

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