Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of estimating when it's possible to plant centaurea is to check out the USDA zone info for Port Huron.

Planting Calendar for Centaurea

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

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

The earliest that you can plant centaurea in Port Huron 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 centaurea and expect a good harvest is probably September. If you wait any later than that and your centaurea may not have a chance to fully mature. You can get started a few weeks earlier by starting your centaurea indoors.

Last Frost Date

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

Keep in mind that USDA zone info for Port Huron is just an average and the actual date of last frost will vary from year to year. Half of the time in Port Huron it frosts late in the year after April 15 so make sure that you are prepared to protect your centaurea in the event of one of those late frosts.

USDA Zone Info for Port Huron

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 Port Huron

You may be interested in your other planting guides for Port Huron.