One of the best tools that you have as gardeners to help us determine 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.

The earliest that you can plant astilbe in Vienna should be determined by using 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 well in some cold which tells us that you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant astilbe in Vienna 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 really do well. You can get started a couple of weeks earlier by starting your astilbe indoors.

Last Frost Date

On average the last frost is on April 15 in Vienna. In the coldest months of winter you can expect an average low temperature of 0°F.

Since the USDA zone info for Vienna is an average the actual date of last frost changes from year to year. Since half of the time in Vienna last frost occurs after April 15 be ready to protect your astilbe if you have a late frost.

USDA Zone Info for Vienna

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Vienna

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