Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant achillea in Wilsonville should be determined by using the USDA zone info.

Planting Calendar for Achillea

Frost tolerance for achillea:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since achillea do well in cold you can plant them a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant achillea in Wilsonville 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 achillea and expect a good harvest is probably September. Any later than that and your achillea may not have a chance to grow to maturity. If you are starting your achillea indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Wilsonville may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Wilsonville last frost occurs after March 15 so make sure that you are ready to protect your achillea 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.