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

You can determine when you can plant astilbe in South Milwaukee 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 are barely cold tolerant which tells us that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant astilbe in South Milwaukee 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. You can get started a little bit earlier by starting your astilbe indoors.

Last Frost Date

On average the last frost is on April 15 in South Milwaukee. It might get as low as -15°F during the coldest months of winter.

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

USDA Zone Info for South Milwaukee

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

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

Plants to Grow in South Milwaukee

You may be interested in your other planting guides for South Milwaukee.