One of the first steps you take when you are figuring out your gardening schedule is find your 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.

By referring to the USDA zone info for Charles Town it's a good idea to figure out when it's a good idea to plant astilbe.

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 tells us that you can plant them slightly earlier than more sensitive plants.

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

Last Frost Date

The average date of last frost is April 15 in Charles Town. It might get as low as -5°F during the coldest months of winter.

Remember that USDA zone info for Charles Town is an average and the actual date of last frost changes from year to year. Half of the time in Charles Town it frosts late in the year after April 15 so be sure to be ready to cover your astilbe in the event of one of those late frosts.

USDA Zone Info for Charles Town

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Charles Town

You may be interested in your other planting guides for Charles Town.