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

By looking at the USDA zone info for Charles City it's possible to determine when it's a good idea 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.

Centaurea are moderately cold tolerant which tells us that you can start planting them earlier than other plants that might not handle the cold.

The earliest that you can plant centaurea in Charles City 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. You probably don't want to wait any later than that or else your centaurea may not have a chance to grow to maturity. If you are starting your centaurea indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Charles City. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Charles City is just an average the actual date of last frost is different every year. Half of the time in Charles City there is a last frost after April 15 so make sure that you are prepared to protect your centaurea if you have a surprise late frost.

USDA Zone Info for Charles City

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 Charles City

You may be interested in your other planting guides for Charles City.