The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Holly you can determine when it's possible to plant columbine by using the USDA zone info.

Planting Calendar for Columbine

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

Columbine can survive in a little bit of cold which means that you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant columbine in Holly 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 few 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 Holly. You can expect an average low temperature of -10°F in the coldest months of winter.

It's important to remember that USDA zone info for Holly is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Holly you get surprised by a frost after April 15 so make sure that you are prepared to cover your columbine if you have a surprise late frost.

USDA Zone Info for Holly

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Holly

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