One of the best tools that you have as gardeners to help us estimate 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 can estimate when to plant sunflowers in Columbia by using the USDA zone info.

Planting Calendar for Sunflowers

Frost tolerance for sunflowers:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since sunflowers do not do well in cold weather it is important to wait until after all chance of frost has passed before you can plant them.

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

The last month that you can plant sunflowers and expect a good harvest is probably August. If you wait any later than that and your sunflowers may not have a chance to fully mature. You can get started a few weeks earlier by starting your sunflowers indoors.

Last Frost Date

The average date of last frost is April 15 in Columbia. In the coldest months of winter you can expect an average low temperature of -5°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Columbia and it changes from year to year. Half of the time in Columbia last frost occurs after April 15 so just be sure to be ready to protect your sunflowers in the event of one of those late frosts.

USDA Zone Info for Columbia

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Columbia

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