One of the best tools that you have as gardeners to help us figure out 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 should be able to determine when it's possible to plant astilbe by using the USDA zone info for Campbell.

Planting Calendar for Astilbe

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

Astilbe are barely cold tolerant which means that you can plant them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant astilbe in Campbell 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 astilbe and expect a good harvest is probably September. You probably don't want to wait any later than that or else your astilbe may not have a chance to really do well. You can get started a couple of weeks earlier by starting your astilbe indoors.

Last Frost Date

The average date of last frost is February 15 in Campbell. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for Campbell may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Campbell it frosts late in the year after February 15 so always be ready to protect your astilbe in the event of one of those late frosts.

USDA Zone Info for Campbell

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 Campbell

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