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

In Hillsborough you can figure out when it's the best time to plant centaurea by referring to 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 earlier in the year because they are moderately cold tolerant.

The earliest that you can plant centaurea in Hillsborough 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 few weeks earlier by starting your centaurea indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Hillsborough. In the coldest months of winter you can expect an average low temperature of 5°F.

Since the USDA zone info for Hillsborough is not always accurate the actual date of last frost changes from year to year. Since half of the time in Hillsborough there is a last frost after April 15 be ready to cover your centaurea if you have one of those late frosts.

USDA Zone Info for Hillsborough

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Hillsborough

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