Before planting it is a good idea to find your USDA Zone info to determine 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.

A common way of making a decision about when it's a good idea to plant astilbe is to refer to the USDA zone info for Chehalis.

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 get them planted just a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant astilbe in Chehalis is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant astilbe and expect a good harvest is probably August. Any later than that and your astilbe may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your astilbe indoors.

Last Frost Date

The average date of last frost is March 15 in Chehalis. You can expect an average low temperature of 10°F in the coldest months of winter.

Keep in mind that USDA zone info for Chehalis is not always accurate and the actual date of last frost is different every year. Since half of the time in Chehalis it frosts late in the year after March 15 be ready to cover your astilbe in the event of one of those late frosts.

USDA Zone Info for Chehalis

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Chehalis

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