One of the first steps you take when you are estimating 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.

You will be able to estimate when to plant torenia by using the USDA zone info for Petaluma.

Planting Calendar for Torenia

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

It's probably not a good idea to plant torenia until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant torenia in Petaluma 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 couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Petaluma is just an average the actual date of last frost will vary from year to year. Half of the time in Petaluma you get a frost after February 15 so make sure that you are ready to protect your torenia if you have a late frost.

USDA Zone Info for Petaluma

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 Petaluma

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