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.

By using the USDA zone info for South Haven you should be able to estimate when it's the best time to plant phlox.

Planting Calendar for Phlox

Frost tolerance for phlox:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant phlox a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant phlox in South Haven 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 phlox and expect a good harvest is probably September. You probably don't want to wait any later than that or else your phlox may not have a chance to fully mature. Starting your phlox indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In South Haven the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

Since the USDA zone info for South Haven is just an average the actual date of last frost will vary from year to year. Since half of the time in South Haven it frosts late in the year after April 15 be ready to cover your phlox in the event of a surprise 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.