One of the first steps you take when you are making a decision about 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.

In Lewistown you can estimate when it's the best time to plant achillea by referring to 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.

You can plant achillea quite a bit earlier in the year because they do well in cold.

The earliest that you can plant achillea in Lewistown 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 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 Lewistown. You should expect an average low temperature of -5°F in the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Lewistown and it will vary from year to year. Half of the time in Lewistown there is a last frost after April 15 so be sure to be ready to protect your achillea if you have a surprise late frost.

USDA Zone Info for Lewistown

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 Lewistown

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