The USDA Zone info is a great tool for gardeners to help us estimate 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.

A common way of determining when it's a good idea to plant copperleaf is to examine the USDA zone info for Havre.

Planting Calendar for Copperleaf

Frost tolerance for copperleaf:	Not tolerant of frost.
When to plant:	After the last frost.

It's a bad idea to plant copperleaf until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant copperleaf in Havre is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant copperleaf and expect a good harvest is probably August. If you wait any later than that and your copperleaf may not have a chance to grow to maturity. If you are starting your copperleaf 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. You should expect an average low temperature of -30°F in the coldest months of winter.

Remember that USDA zone info for Havre is just an average and the actual date of last frost changes from year to year. Half of the time in Havre you get a frost after May 15 so be sure to be ready to protect your copperleaf if you have 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.