One of the first steps you take when you are estimating your gardening schedule is find your 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 USDA zone info for Helena can be read to determine when you can plant garden mums.

Planting Calendar for Garden Mums

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

Garden Mums are moderately cold tolerant which means that you can plant them earlier than more sensitive plants.

The earliest that you can plant garden mums 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 garden mums and expect a good harvest is probably September. You probably don't want to wait any later than that or else your garden mums may not have a chance to really do well. If you are starting your garden mums 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.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Helena and it is different every year. Since half of the time in Helena last frost occurs after March 15 be ready to cover your garden mums if you have one of those late frosts.

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.