One of the best tools that you have as gardeners to help us determine 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 determining when it's possible to plant bishop's weed is to examine the USDA zone info for Polson.

Planting Calendar for Bishop's Weed

Frost tolerance for bishop's weed:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since bishop's weed are very cold tolerant you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant bishop's weed in Polson 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 bishop's weed and expect a good harvest is probably September. Any later than that and your bishop's weed may not have a chance to really do well. Starting your bishop's weed indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Polson the average date of last frost happens on April 15. You should expect an average low temperature of -10°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Polson is not always accurate and the actual date of last frost is different every year. Half of the time in Polson there is a last frost after April 15 so make sure that you are prepared to cover your bishop's weed if you have a surprise late frost.

USDA Zone Info for Polson

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Polson

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