The USDA Zone info is a great tool for gardeners to help us figure out your gardening 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 Cortland should be read to determine when 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.

Columbine do well in mild cold which tells us that you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant columbine in Cortland 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 columbine and expect a good harvest is probably September. If you wait any later than that and your columbine may not have a chance to grow to maturity. Starting your columbine indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Cortland is just an average the actual date of last frost is different every year. Since half of the time in Cortland last frost occurs after April 15 be ready to cover your columbine in the event of a late frost.

USDA Zone Info for Cortland

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Cortland

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