One of the best tools that you have as gardeners to help us estimate 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 way of making a decision about when you can plant bishop's weed is to check out the USDA zone info for Havre.

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.

You can plant bishop's weed a lot earlier in the year because they do well in cold.

The earliest that you can plant bishop's weed in Havre 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 bishop's weed and expect a good harvest is probably August. You probably don't want to wait any later than that or else your bishop's weed may not have a chance to fully mature. If you are starting your bishop's weed indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Havre. It might get as low as -30°F during the coldest months of winter.

Since the USDA zone info for Havre may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Havre it frosts late in the year after May 15 so be sure to be ready to cover your bishop's weed in the event of a late frost.

USDA Zone Info for Havre

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 Havre

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