One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

In Columbia Falls you can determine when it's a good idea to plant dianthus by checking out the USDA zone info.

Planting Calendar for Dianthus

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

Dianthus are moderately cold tolerant which tells us that you can plant them a little bit earlier than other frost tender plants.

The earliest that you can plant dianthus in Columbia Falls 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 dianthus and expect a good harvest is probably September. If you wait any later than that and your dianthus may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your dianthus indoors.

Last Frost Date

The average date of last frost is April 15 in Columbia Falls. It might get as low as -20°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Columbia Falls and it can change quite a bit from year to year. Half of the time in Columbia Falls it frosts late in the year after April 15 so always be ready to protect your dianthus in the event of one of those late frosts.

USDA Zone Info for Columbia Falls

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 Columbia Falls

You may be interested in your other planting guides for Columbia Falls.