The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. 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 used to figure out when it's a good idea to plant cilantro.

Planting Calendar for Cilantro

Frost tolerance for cilantro:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant cilantro slightly earlier in the year because they do ok in moderate cold.

The earliest that you can plant cilantro 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 cilantro and expect a good harvest is probably August. If you wait any later than that and your cilantro may not have a chance to really do well. You can get started a little bit earlier by starting your cilantro indoors.

Last Frost Date

The average date of last frost is March 15 in Helena. 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 just an average because it is based on the USDA zone info for Helena and it changes from year to year. Since half of the time in Helena it frosts late in the year after March 15 be ready to cover your cilantro in the event of 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.