The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant mecardonia in Helena can be determined by checking out the USDA zone info.

Planting Calendar for Mecardonia

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

Since mecardonia are not cold tolerant it is important to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant mecardonia 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 mecardonia and expect a good harvest is probably August. If you wait any later than that and your mecardonia may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your mecardonia indoors.

Last Frost Date

In Helena the average date of last frost happens on May 15. You can expect an average low temperature of -25°F in the coldest months of winter.

Always keep in mind that USDA zone info for Helena is just an average 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 protect your mecardonia if you have a 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.