Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Zone 1b can be reffered to in order to figure out when it's a good idea to plant columbine.

Planting Calendar for Columbine

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

Since columbine are moderately cold tolerant you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant columbine in Zone 1b is May. However, you really should wait until June if you don't want to take any chances.

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

Last Frost Date

On average the last frost is on June 15 in Zone 1b. You can expect an average low temperature of -55°F in the coldest months of winter.

It's important to remember that USDA zone info for Zone 1b may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Zone 1b it frosts late in the year after June 15 be ready to cover your columbine in the event of a surprise late frost.

USDA Zone Info for Zone 1b

Here is the info for USDA Zone 1b.

Average Date of Last Frost (spring)	June 15
Average Date of First Frost (fall)	July 15
Lowest Expected Low	-55°F
Highest Expected Low	-50°F

This means that on a really cold year, the coldest it will get is -55°F. On most years you should be prepared to experience lows near -50°F.

Plants to Grow in Zone 1b

You may be interested in your other planting guides for Zone 1b.