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

By checking out the USDA zone info for Washington you should be able to determine when you can plant torenia.

Planting Calendar for Torenia

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

Torenia do not do well in cold weather which tells us that you need 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 Washington 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. 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 few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Washington. You can expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Washington may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Washington you get a frost after April 15 be ready to protect your torenia in the event of one of those late frosts.

USDA Zone Info for Washington

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Washington

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