One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of getting a good idea when it's the best time to plant achillea is to examine the USDA zone info for Berthoud.

Planting Calendar for Achillea

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

You can plant achillea a lot earlier in the year because they are very cold tolerant.

The earliest that you can plant achillea in Berthoud 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. If you wait any later than that and your achillea may not have a chance to grow to maturity. Starting your achillea indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Berthoud. It might get as low as -15°F during the coldest months of winter.

Always keep in mind that USDA zone info for Berthoud is an average and the actual date of last frost will vary from year to year. Half of the time in Berthoud it frosts late in the year after April 15 so make sure that you are prepared to cover your achillea in the event of one of those late frosts.

USDA Zone Info for Berthoud

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°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 -10°F.

Plants to Grow in Berthoud

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