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

The first opportunity to plant sunflowers in South Haven can be determined by referring to the USDA zone info.

Planting Calendar for Sunflowers

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

Sunflowers are not cold tolerant which means that you really should wait until it warms up after the last frost before you can plant them.

The earliest that you can plant sunflowers in South Haven 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 really do well. Starting your sunflowers indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in South Haven. You should expect an average low temperature of -5°F in the coldest months of winter.

Always keep in mind that USDA zone info for South Haven is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in South Haven you get surprised by a frost after April 15 be ready to cover your sunflowers if you have a late frost.

USDA Zone Info for South Haven

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 South Haven

You may be interested in your other planting guides for South Haven.