Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. 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 Columbia Falls you should be able to figure out when it's a good idea to plant rudbeckia.

Planting Calendar for Rudbeckia

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

Rudbeckia do ok in mild cold which tells us that you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant rudbeckia 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 rudbeckia and expect a good harvest is probably September. Any later than that and your rudbeckia may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your rudbeckia indoors.

Last Frost Date

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

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Columbia Falls and it will vary from year to year. Since half of the time in Columbia Falls you get surprised by a frost after April 15 be ready to protect your rudbeckia 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.