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.

It's possible to estimate when it's possible to plant phlox by using the USDA zone info for Kalispell.

Planting Calendar for Phlox

Frost tolerance for phlox:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Phlox do well in moderate cold which means that you can plant them earlier than other plants that might not handle the cold.

The earliest that you can plant phlox in Kalispell is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant phlox and expect a good harvest is probably September. Any later than that and your phlox may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your phlox indoors.

Last Frost Date

In Kalispell the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Kalispell is just an average the actual date of last frost is different every year. Half of the time in Kalispell you get surprised by a frost after April 15 so just be sure to be ready to protect your phlox in the event of a surprise late frost.

USDA Zone Info for Kalispell

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Kalispell

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