Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of figuring out when it's the best time to plant centaurea is to examine the USDA zone info for Galesburg.

Planting Calendar for Centaurea

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

Centaurea tend to make it in moderate cold which means that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant centaurea in Galesburg 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. Any later than that and your centaurea may not have a chance to fully mature. 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 Galesburg. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Galesburg may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Galesburg you get a frost 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 Galesburg

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 Galesburg

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