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

By referring to the USDA zone info for Wilsonville you should be able to figure out 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.

Since astilbe do ok in moderate cold you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant astilbe in Wilsonville 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 fully mature. You can get started a few weeks earlier by starting your astilbe indoors.

Last Frost Date

On average the last frost has passed is on March 15 in Wilsonville. You can expect an average low temperature of 15°F in the coldest months of winter.

It's important to remember that USDA zone info for Wilsonville is just an average and the actual date of last frost will vary from year to year. Since half of the time in Wilsonville it frosts late in the year after March 15 be ready to protect your astilbe if you have a surprise late frost.

USDA Zone Info for Wilsonville

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 Wilsonville

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