Before planting it is a good idea to find your USDA Zone info to figure out 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.

One way of determining when you can plant columbine is to examine the USDA zone info for Oak Forest.

Planting Calendar for Columbine

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

You can plant columbine a little bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant columbine in Oak Forest 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. You probably don't want to wait any later than that or else your columbine may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your columbine indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Oak Forest. It might get as low as -15°F during the coldest months of winter.

It's important to remember that USDA zone info for Oak Forest is just an average and the actual date of last frost will vary from year to year. Half of the time in Oak Forest there is a last frost after April 15 so just be sure to be ready to cover your columbine in the event of one of those late frosts.

USDA Zone Info for Oak Forest

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 Oak Forest

You may be interested in your other planting guides for Oak Forest.