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 common way of making a decision about when it's the best time to plant polka dot plant is to refer to the USDA zone info for Havre.

Planting Calendar for Polka Dot Plant

Frost tolerance for polka dot plant:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since polka dot plant are not cold tolerant you must wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant polka dot plant 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 polka dot plant and expect a good harvest is probably August. You probably don't want to wait any later than that or else your polka dot plant may not have a chance to really do well. You can get started a few weeks earlier by starting your polka dot plant indoors.

Last Frost Date

In Havre the average date of last frost happens on May 15. It might get as low as -30°F during the coldest months of winter.

Since the USDA zone info for Havre is not always accurate 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 polka dot plant 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.