When to Plant Centaurea in Janesville, WI

One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant centaurea in Janesville can be determined by reviewing 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.

You can plant centaurea a little bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant centaurea
Possibly ok, but a risky time to plant centaurea
Probably not a good time to plant centaurea

The earliest that you can plant centaurea in Janesville 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. Starting your centaurea indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Janesville the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Janesville is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Janesville you get surprised by a frost after April 15 be ready to protect your centaurea in the event of a late frost.

USDA Zone Info for Janesville

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 Janesville

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