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.

It's a good idea to determine when you can plant jerusalem artichokes by checking out the USDA zone info for Havre.

Planting Calendar for Jerusalem artichokes

Frost tolerance for jerusalem artichokes:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Jerusalem artichokes tend to make it in mild cold which tells us that you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant jerusalem artichokes 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 jerusalem artichokes and expect a good harvest is probably August. If you wait any later than that and your jerusalem artichokes may not have a chance to grow to maturity. You can get started a little bit earlier by starting your jerusalem artichokes indoors.

Last Frost Date

On average all chance of frost has passed is on 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 you get surprised by a frost after May 15 so just be sure to be ready to cover your jerusalem artichokes in the event of one of those late frosts.

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.