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

In Wasco you can figure out when you can plant astilbe by checking out the USDA zone info.

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 do ok in some cold which tells us that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant astilbe in Wasco 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 fully mature. Starting your astilbe indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Wasco the average date of last frost happens on February 15. You should expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Wasco is not always accurate the actual date of last frost changes from year to year. Half of the time in Wasco you get surprised by a frost after February 15 so just be sure to be ready to cover your astilbe in the event of a surprise late frost.

USDA Zone Info for Wasco

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Wasco

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