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

The USDA zone info for North Liberty should be reffered to in order to figure out when it's possible to plant centaurea.

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 other frost tender plants.

The earliest that you can plant centaurea in North Liberty 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 really do well. If you are starting your centaurea indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Just be sure to remember that USDA zone info for North Liberty is just an average and the actual date of last frost is different every year. Since half of the time in North Liberty there is a last frost after April 15 be ready to protect your centaurea in the event of a surprise late frost.

USDA Zone Info for North Liberty

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in North Liberty

You may be interested in your other planting guides for North Liberty.