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 Lewistown you can estimate when it's a good idea to plant yarrow by reviewing 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.

Yarrow are very cold tolerant which means that you can get them planted much earlier than other plants that might not handle the cold.

The earliest that you can plant yarrow 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 yarrow and expect a good harvest is probably September. You probably don't want to wait any later than that or else your yarrow may not have a chance to fully mature. Starting your yarrow 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 Lewistown. You should expect an average low temperature of -5°F in the coldest months of winter.

Keep in mind that USDA zone info for Lewistown is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Lewistown you get surprised by a frost after April 15 so make sure that you are prepared to protect your yarrow in the event of 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.