One of the best tools that you have as gardeners to help us estimate 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.

It's possible to estimate when it's a good idea to plant yarrow by using the USDA zone info for Rhinelander.

Planting Calendar for Yarrow

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

You can plant yarrow a lot earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant yarrow in Rhinelander is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant yarrow and expect a good harvest is probably August. 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

In Rhinelander the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -30°F.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Rhinelander and it is different every year. Half of the time in Rhinelander there is a last frost after May 15 so just be sure to be ready to cover your yarrow if you have one of those late frosts.

USDA Zone Info for Rhinelander

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Rhinelander

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