The USDA Zone info is a great tool for gardeners to help us figure out 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 making a decision about when to plant purple bell vines is to consult the USDA zone info for Polson.

Planting Calendar for Purple Bell Vines

Frost tolerance for purple bell vines:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Purple Bell Vines do ok in moderate cold which means that you can get them planted just a bit earlier than other plants that might not handle the cold.

The earliest that you can plant purple bell vines in Polson is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant purple bell vines and expect a good harvest is probably August. Any later than that and your purple bell vines may not have a chance to grow to maturity. Starting your purple bell vines indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Polson. You should expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Polson is an average and the actual date of last frost is different every year. Since half of the time in Polson last frost occurs after April 15 be ready to protect your purple bell vines if you have one of those late frosts.

USDA Zone Info for Polson

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°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 -5°F.

Plants to Grow in Polson

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