One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Hartland you should be able to estimate 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 just a bit earlier in the year than more sensitive plants.

The earliest that you can plant centaurea in Hartland 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 fully mature. You can get started a couple of weeks earlier by starting your centaurea indoors.

Last Frost Date

In Hartland the average date of last frost happens on April 15. You can expect an average low temperature of -20°F in the coldest months of winter.

It's important to remember that USDA zone info for Hartland is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Hartland there is a last frost after April 15 so just be sure to be ready to protect your centaurea if you have a surprise late frost.

USDA Zone Info for Hartland

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 Hartland

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