One of the first steps you take when you are making a decision about 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.

In Tualatin you can figure out when to plant torenia by referring to the USDA zone info.

Planting Calendar for Torenia

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

Since torenia require warm weather it's necessary to wait until after the last frost before you can plant them.

The earliest that you can plant torenia in Tualatin is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant torenia and expect a good harvest is probably August. Any later than that and your torenia may not have a chance to really do well. You can get started a few weeks earlier by starting your torenia indoors.

Last Frost Date

In Tualatin the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 15°F.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Tualatin and it can change quite a bit from year to year. Since half of the time in Tualatin it frosts late in the year after March 15 be ready to cover your torenia if you have a surprise late frost.

USDA Zone Info for Tualatin

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Tualatin

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