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

A common way of determining when it's possible to plant crassula is to consult the USDA zone info for Helena.

Planting Calendar for Crassula

Frost tolerance for crassula:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since crassula are not cold tolerant you must wait until after the last frost when the weather gets warmer before you can plant them.

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

The last month that you can plant crassula and expect a good harvest is probably August. Any later than that and your crassula may not have a chance to fully mature. If you are starting your crassula indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Helena the average date of last frost happens on March 15. You should expect an average low temperature of 10°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Helena and it changes from year to year. Half of the time in Helena you get a frost after March 15 so be sure to be ready to cover your crassula in the event of a surprise late frost.

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.