The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Washington can be looked at to determine when it's possible to plant stevia.

Planting Calendar for Stevia

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

Stevia are not cold tolerant which tells us that it is necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant stevia 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 stevia and expect a good harvest is probably August. If you wait any later than that and your stevia may not have a chance to really do well. Starting your stevia 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. It might get as low as -15°F during the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Washington and it will vary from year to year. Since half of the time in Washington last frost occurs after April 15 be ready to protect your stevia in the event of a surprise late frost.

USDA Zone Info for Washington

Here is the info for USDA Zone 5b.

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

Plants to Grow in Washington

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