One of the first steps you take when you are getting a good idea 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.

The USDA zone info for Marathon should be reviewed to determine when you can plant astilbe.

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.

Since astilbe are one of those plants that can tolerate a tiny bit of cold weather you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

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

The last month that you can plant astilbe and expect a good harvest is probably November. You probably don't want to wait any later than that or else your astilbe may not have a chance to really do well. You can get started a little bit earlier by starting your astilbe indoors.

Last Frost Date

In Marathon it never frosts. It might get as low as 45°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Marathon and it will vary from year to year. Since it never frosts in Marathon you do not have to be ready to protect your astilbe if you have one of those late frosts.

USDA Zone Info for Marathon

Here is the info for USDA Zone 11b.

Average Date of Last Frost (spring)	Never
Average Date of First Frost (fall)	Never
Lowest Expected Low	45°F
Highest Expected Low	50°F

This means that on a really cold year, the coldest it will get is 45°F. On most years you should be prepared to experience lows near 50°F.

Plants to Grow in Marathon

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