One of the best tools that you have as gardeners to help us estimate 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.

The USDA zone info for Charles City should be used to estimate 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.

Since columbine do well in moderate cold you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant columbine in Charles City 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. Any later than that and your columbine may not have a chance to fully mature. If you are starting your columbine indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

It's important to remember that USDA zone info for Charles City is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Charles City last frost occurs after April 15 so just be sure to be ready to cover your columbine if you have one of those late frosts.

USDA Zone Info for Charles City

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 Charles City

You may be interested in your other planting guides for Charles City.