Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. 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 making a decision about when to plant sunflowers is to look at the USDA zone info for Vandalia.

Planting Calendar for Sunflowers

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

It's probably not a good idea to plant sunflowers until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant sunflowers in Vandalia 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. You probably don't want to wait any later than that or else your sunflowers may not have a chance to really do well. Starting your sunflowers indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Vandalia. You should expect an average low temperature of -10°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Vandalia and it changes from year to year. Half of the time in Vandalia you get surprised by a frost 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 Vandalia

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 Vandalia

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