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.

A way of estimating when to plant achillea is to consult the USDA zone info for Oak Ridge.

Planting Calendar for Achillea

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

Achillea do well in cold which tells us that you can get them planted much earlier than more sensitive plants.

The earliest that you can plant achillea in Oak Ridge 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. You probably don't want to wait any later than that or else your achillea may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your achillea indoors.

Last Frost Date

The average date of last frost is April 15 in Oak Ridge. It might get as low as 0°F during the coldest months of winter.

Keep in mind that USDA zone info for Oak Ridge is an average and the actual date of last frost will vary from year to year. Half of the time in Oak Ridge there is a last frost after April 15 so always be ready to protect your achillea if you have a surprise late frost.

USDA Zone Info for Oak Ridge

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Oak Ridge

You may be interested in your other planting guides for Oak Ridge.