One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of figuring out when it's possible to plant browallia is to consult the USDA zone info for Washington.

Planting Calendar for Browallia

Frost tolerance for browallia:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's a bad idea to plant browallia until after the last frost because they do not do well in cold weather.

The earliest that you can plant browallia 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 browallia and expect a good harvest is probably August. If you wait any later than that and your browallia may not have a chance to fully mature. If you are starting your browallia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Washington the average date of last frost happens on April 15. It might get as low as 0°F during the coldest months of winter.

Keep in mind that USDA zone info for Washington is an average and the actual date of last frost changes from year to year. Since half of the time in Washington you get a frost after April 15 be ready to cover your browallia in the event of one of those late frosts.

USDA Zone Info for Washington

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°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.