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

You will be able to determine when to plant verbena by checking out the USDA zone info for Columbia.

Planting Calendar for Verbena

Frost tolerance for verbena:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Verbena do ok in some cold which means that you can plant them just a tiny bit earlier in the year than more sensitive plants.

The earliest that you can plant verbena in Columbia is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant verbena and expect a good harvest is probably August. Any later than that and your verbena may not have a chance to fully mature. Starting your verbena indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Columbia may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Columbia it frosts late in the year after April 15 so make sure that you are prepared to cover your verbena in the event of one of those late frosts.

USDA Zone Info for Columbia

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 Columbia

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