When to Plant Onions in Laurel, MT

One of the best tools that you have as gardeners to help us determine 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.

The first chance to plant onions in Laurel should be estimated by using the USDA zone info.


Planting Calendar for Onions

Frost tolerance for onions: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

Onions can survive in pretty solid cold which means that you can plant them much earlier in the year than more sensitive plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant onions
Possibly ok, but a risky time to plant onions
Probably not a good time to plant onions

The earliest that you can plant onions in Laurel 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 onions and expect a good harvest is probably August. You probably don't want to wait any later than that or else your onions may not have a chance to grow to maturity. Starting your onions indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Laurel the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -25°F.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Laurel and it is different every year. Since half of the time in Laurel you get a frost after May 15 be ready to protect your onions in the event of one of those late frosts.

USDA Zone Info for Laurel

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-25°F
Highest Expected Low-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Laurel

You may be interested in your other planting guides for Laurel.