When to Plant Astilbe in Germantown, WI

One of the first steps you take when you are estimating 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.

In Germantown you can figure out when it's possible to plant astilbe by reviewing 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.

You can plant astilbe slightly earlier in the year because they are barely cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant astilbe
Possibly ok, but a risky time to plant astilbe
Probably not a good time to plant astilbe

The earliest that you can plant astilbe in Germantown 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. If you wait 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

The average date of last frost is April 15 in Germantown. You should expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Germantown is an average the actual date of last frost is different every year. Half of the time in Germantown you get surprised by a frost after April 15 so just be sure to be ready to protect your astilbe if you have one of those late frosts.

USDA Zone Info for Germantown

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°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 -15°F.

Plants to Grow in Germantown

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