The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to figure out when it's the best time to plant centaurea by looking at the USDA zone info for Washington.

Planting Calendar for Centaurea

Frost tolerance for centaurea:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

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

The earliest that you can plant centaurea 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 centaurea and expect a good harvest is probably September. You probably don't want to wait any later than that or else your centaurea may not have a chance to fully mature. Starting your centaurea indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Washington the average date of last frost happens on March 15. It might get as low as 10°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is not always accurate 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 you get a frost after March 15 be ready to protect your centaurea in the event of a surprise late frost.

USDA Zone Info for Washington

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Washington

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