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.

The USDA zone info for Patterson can be reviewed to determine when it's possible to 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.

Astilbe do ok in moderate cold which tells us that you can plant them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant astilbe in Patterson 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. Any later than that and 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 Patterson the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

It's important to remember that USDA zone info for Patterson is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Patterson you get a frost after February 15 so always be ready to protect your astilbe if you have one of those late frosts.

USDA Zone Info for Patterson

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°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 30°F.

Plants to Grow in Patterson

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