One of the first steps you take when you are estimating 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.

The best time to plant brussels sprouts in Helena should be estimated by looking at the USDA zone info.

Planting Calendar for Brussels Sprouts

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

You can plant brussels sprouts a little bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant brussels sprouts in Helena is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant brussels sprouts and expect a good harvest is probably September. If you wait any later than that and your brussels sprouts may not have a chance to fully mature. If you are starting your brussels sprouts indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Helena. You can expect an average low temperature of 10°F in the coldest months of winter.

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 last frost occurs after March 15 so always be ready to cover your brussels sprouts if you have a late frost.

USDA Zone Info for Helena

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Helena

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