The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of estimating when it's possible to plant astilbe is to examine the USDA zone info for Hudson.

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 one of those plants that can tolerate a tiny bit of cold weather which means that you can plant them slightly earlier than more sensitive plants.

The earliest that you can plant astilbe in Hudson is April. However, you really should wait until May 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 fully mature. You can get started a few weeks earlier by starting your astilbe indoors.

Last Frost Date

In Hudson the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -25°F.

It's important to remember that USDA zone info for Hudson is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Hudson last frost occurs after May 15 so always be ready to protect your astilbe in the event of a surprise late frost.

USDA Zone Info for Hudson

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Hudson

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