One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By reviewing the USDA zone info for Polson it's a good idea to determine when it's a good idea to plant cardinal flower.

Planting Calendar for Cardinal Flower

Frost tolerance for cardinal flower:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Cardinal Flower require warm weather which means that it's necessary to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant cardinal flower in Polson 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 cardinal flower and expect a good harvest is probably August. If you wait any later than that and your cardinal flower may not have a chance to grow to maturity. You can get started a little bit earlier by starting your cardinal flower indoors.

Last Frost Date

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

It's important to remember that USDA zone info for Polson is not always accurate and the actual date of last frost is different every year. Since half of the time in Polson you get a frost after April 15 be ready to cover your cardinal flower if you have a late frost.

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.