The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant centaurea in Portage can be estimated by using the USDA zone info.

Planting Calendar for Centaurea

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

Since centaurea do well in moderate cold you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant centaurea in Portage 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 grow to maturity. You can get started a little bit earlier by starting your centaurea indoors.

Last Frost Date

The average date of last frost is April 15 in Portage. In the coldest months of winter you can expect an average low temperature of -20°F.

It's important to remember that USDA zone info for Portage is not always accurate and the actual date of last frost is different every year. Half of the time in Portage last frost occurs after April 15 so just be sure to be ready to cover your centaurea in the event of one of those late frosts.

USDA Zone Info for Portage

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Portage

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