One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant yarrow in Oregon should be determined by referring to the USDA zone info.

Planting Calendar for Yarrow

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

You can plant yarrow quite a bit earlier in the year because they are very cold tolerant.

The earliest that you can plant yarrow in Oregon 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 yarrow and expect a good harvest is probably September. If you wait any later than that and your yarrow may not have a chance to fully mature. You can get started a few weeks earlier by starting your yarrow indoors.

Last Frost Date

The average date of last frost is April 15 in Oregon. It might get as low as -5°F during the coldest months of winter.

Always keep in mind that USDA zone info for Oregon is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Oregon there is a last frost after April 15 be ready to cover your yarrow if you have a late frost.

USDA Zone Info for Oregon

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Oregon

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