One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Smithfield you will be able 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.

Since columbine do well in moderate cold you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant columbine in Smithfield 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 fully mature. Starting your columbine indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost is on March 15 in Smithfield. In the coldest months of winter you can expect an average low temperature of 10°F.

Since the USDA zone info for Smithfield is just an average the actual date of last frost will vary from year to year. Half of the time in Smithfield last frost occurs after March 15 so make sure that you are ready to protect your columbine if you have one of those late frosts.

USDA Zone Info for Smithfield

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Smithfield

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