One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when to plant astilbe is to look at the USDA zone info for Bay City.

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 ok in mild cold which means that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant astilbe in Bay City is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant astilbe and expect a good harvest is probably September. If you wait any later than that and 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 all chance of frost has passed is on February 15 in Bay City. It might get as low as 20°F during the coldest months of winter.

Always keep in mind that USDA zone info for Bay City is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Bay City you get a frost after February 15 be ready to protect your astilbe if you have a late frost.

USDA Zone Info for Bay City

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°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 25°F.

Plants to Grow in Bay City

You may be interested in your other planting guides for Bay City.