When to Plant Carrots in Helena, MT

One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to estimate when it's possible to plant carrots by looking at the USDA zone info for Helena.


Planting Calendar for Carrots

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

You can plant carrots a little bit earlier in the year because they do well in moderate cold.

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

The earliest that you can plant carrots in Helena 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 carrots and expect a good harvest is probably August. If you wait any later than that and your carrots may not have a chance to fully mature. You can get started a little bit earlier by starting your carrots indoors.

Last Frost Date

In Helena 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.

It's important to remember that USDA zone info for Helena may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Helena you get a frost after May 15 so make sure that you are prepared to protect your carrots if you have a surprise late frost.

USDA Zone Info for Helena

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 Helena

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