Before planting it is a good idea to find your USDA Zone info to estimate your garden 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 Costa Mesa should be reffered to in order to determine when it's a good idea to plant achillea.

Planting Calendar for Achillea

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

Since achillea do well in cold you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant achillea in Costa Mesa is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant achillea and expect a good harvest is probably October. If you wait any later than that and your achillea may not have a chance to fully mature. Starting your achillea indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on January 31 in Costa Mesa. You can expect an average low temperature of 35°F in the coldest months of winter.

Since the USDA zone info for Costa Mesa is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Costa Mesa you get a frost after January 31 be ready to cover your achillea in the event of a late frost.

USDA Zone Info for Costa Mesa

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in Costa Mesa

You may be interested in your other planting guides for Costa Mesa.