One of the first steps you take when you are making a decision about your gardening schedule is find your 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.

The first opportunity to plant oleander in Havre can be determined by reviewing the USDA zone info.

Planting Calendar for Oleander

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

You really shouldn't plant oleander until after the last frost when the weather gets warmer because they do not do well in cold weather.

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

Last Frost Date

On average all chance of frost has passed is on May 15 in Havre. You can expect an average low temperature of -30°F in 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 changes from year to year. Since half of the time in Havre you get a frost after May 15 be ready to protect your oleander if you have a surprise 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.