Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Havre you can determine when you can plant welsh onion by referring to the USDA zone info.

Planting Calendar for Welsh onion

Frost tolerance for welsh onion:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since welsh onion are barely cold tolerant you can plant them slightly earlier in the year than other plants that might not handle the cold.

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

The last month that you can plant welsh onion and expect a good harvest is probably August. You probably don't want to wait any later than that or else your welsh onion may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your welsh onion indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Havre. In the coldest months of winter you should expect an average low temperature of -30°F.

Keep in mind that USDA zone info for Havre is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Havre you get surprised by a frost after May 15 so always be ready to cover your welsh onion 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.