One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

You can estimate when it's possible to plant snow-in summer in Helena by looking at the USDA zone info.

Planting Calendar for Snow-in Summer

Frost tolerance for snow-in summer:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant snow-in summer a little earlier in the year because they do well in moderate cold.

The earliest that you can plant snow-in summer 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 snow-in summer and expect a good harvest is probably September. Any later than that and your snow-in summer may not have a chance to really do well. You can get started a few weeks earlier by starting your snow-in summer indoors.

Last Frost Date

On average the last frost has passed is on March 15 in Helena. You should expect an average low temperature of 10°F in the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year 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 you get surprised by a frost after March 15 be ready to protect your snow-in summer 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.