One of the best tools that you have as gardeners to help us figure out 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.

The USDA zone info for Washington should be reviewed to figure out when it's possible to plant ajuga.

Planting Calendar for Ajuga

Frost tolerance for ajuga:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Ajuga are one of those plants that can tolerate quite a bit of cold weather which tells us that you can start planting them much earlier than plants that are more sensitive to the cold.

The earliest that you can plant ajuga in Washington is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant ajuga and expect a good harvest is probably September. You probably don't want to wait any later than that or else your ajuga may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your ajuga indoors.

Last Frost Date

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

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Washington and it is different every year. Half of the time in Washington you get surprised by a frost after April 15 so make sure that you are prepared to cover your ajuga in the event of a late frost.

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.