One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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 Washington you can determine when it's a good idea to plant canna by referring to the USDA zone info.

Planting Calendar for Canna

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

It's probably a bad idea to plant canna until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant canna 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 canna and expect a good harvest is probably August. If you wait any later than that and your canna may not have a chance to really do well. If you are starting your canna indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Washington. You should expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Washington is just an average and the actual date of last frost changes from year to year. Half of the time in Washington it frosts late in the year after April 15 so make sure that you are ready to cover your canna 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.