One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to determine when it's the best time to plant trachelium by using the USDA zone info for Missoula.

Planting Calendar for Trachelium

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

Since trachelium do not do well in cold weather you must wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant trachelium in Missoula 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 trachelium and expect a good harvest is probably August. You probably don't want to wait any later than that or else your trachelium may not have a chance to fully mature. You can get started a few weeks earlier by starting your trachelium indoors.

Last Frost Date

The average date of last frost is April 15 in Missoula. You should expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that USDA zone info for Missoula is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Missoula you get a frost after April 15 so always be ready to cover your trachelium if you have a surprise late frost.

USDA Zone Info for Missoula

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Missoula

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