The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Caldwell you can determine when you can plant achillea by checking out 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.

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

The earliest that you can plant achillea in Caldwell 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 really do well. Starting your achillea indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Caldwell. In the coldest months of winter you can expect an average low temperature of -5°F.

It's important to remember that USDA zone info for Caldwell is just an average and the actual date of last frost is different every year. Since half of the time in Caldwell you get surprised by a frost after April 15 be ready to cover your achillea if you have one of those late frosts.

USDA Zone Info for Caldwell

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 Caldwell

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