The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. 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 broccoli in Helena should be figured out by using the USDA zone info.

Planting Calendar for Broccoli

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

Broccoli can survive in mild cold which tells us that you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant broccoli 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 broccoli and expect a good harvest is probably September. Any later than that and your broccoli may not have a chance to grow to maturity. If you are starting your broccoli indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Helena the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 10°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Helena and it will vary from year to year. Half of the time in Helena last frost occurs after March 15 so be sure to be ready to cover your broccoli 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.