The USDA Zone info is a great tool for gardeners to help us determine 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.

You should be able to determine when it's the best time to plant purple coneflower by using the USDA zone info for Cupertino.

Planting Calendar for Purple Coneflower

Frost tolerance for purple coneflower:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Purple Coneflower do well in very little cold which means that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant purple coneflower in Cupertino 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 purple coneflower and expect a good harvest is probably September. Any later than that and your purple coneflower may not have a chance to really do well. If you are starting your purple coneflower indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Cupertino the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Cupertino and it is different every year. Since half of the time in Cupertino there is a last frost after February 15 be ready to protect your purple coneflower if you have one of those late frosts.

USDA Zone Info for Cupertino

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 Cupertino

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