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.

A way of figuring out when it's possible to plant columbine is to use the USDA zone info for Kent.

Planting Calendar for Columbine

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

Columbine are one of those plants that can tolerate a little bit of cold weather which means that you can plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant columbine in Kent 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 really do well. If you are starting your columbine indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Kent. It might get as low as -10°F during the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Kent and it can change quite a bit from year to year. Since half of the time in Kent there is a last frost after April 15 be ready to cover your columbine if you have a surprise late frost.

USDA Zone Info for Kent

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 Kent

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