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

You can estimate when it's a good idea to plant achillea in Sunnyvale by looking at the USDA zone info.

Planting Calendar for Achillea

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

Achillea do ok in a bit of cold which means that you can plant them quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant achillea in Sunnyvale 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. You probably don't want to wait any later than that or else your achillea may not have a chance to grow to maturity. Starting your achillea indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Sunnyvale the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Sunnyvale is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Sunnyvale you get a frost after February 15 be ready to cover your achillea in the event of one of those late frosts.

USDA Zone Info for Sunnyvale

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Sunnyvale

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