The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Havre you should be able to figure out when you can plant scaevola.

Planting Calendar for Scaevola

Frost tolerance for scaevola:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You really shouldn't plant scaevola until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant scaevola 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 scaevola and expect a good harvest is probably August. If you wait any later than that and your scaevola may not have a chance to really do well. You can get started a couple of weeks earlier by starting your scaevola indoors.

Last Frost Date

On average all chance of frost has passed is on May 15 in Havre. You should expect an average low temperature of -30°F in 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. Since half of the time in Havre it frosts late in the year after May 15 be ready to cover your scaevola 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.