The USDA Zone info is a great tool for gardeners to help us estimate 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 earliest that you can plant jasmine in Helena should be determined by using the USDA zone info.

Planting Calendar for Jasmine

Frost tolerance for jasmine:	Not tolerant of frost.
When to plant:	After the last frost.

Jasmine require warm weather which tells us that it's important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant jasmine in Helena is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant jasmine and expect a good harvest is probably August. You probably don't want to wait any later than that or else your jasmine may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your jasmine indoors.

Last Frost Date

On average all chance of frost has passed is on May 15 in Helena. You should expect an average low temperature of -25°F in the coldest months of winter.

Remember that USDA zone info for Helena is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Helena you get surprised by a frost after May 15 be ready to cover your jasmine in the event of a surprise late frost.

USDA Zone Info for Helena

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Helena

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