One of the best tools that you have as gardeners to help us determine 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 Auburn can be used to figure out when 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 other frost tender plants.

The earliest that you can plant astilbe in Auburn 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. If you wait any later than that and your astilbe may not have a chance to grow to maturity. If you are starting your astilbe indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Auburn. You should expect an average low temperature of 15°F in the coldest months of winter.

Always keep in mind that USDA zone info for Auburn may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Auburn it frosts late in the year after March 15 be ready to cover your astilbe in the event of one of those late frosts.

USDA Zone Info for Auburn

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Auburn

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