One of the first steps you take when you are estimating 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 USDA zone info for Watertown can be reviewed to figure out 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.

You can plant centaurea just a bit earlier in the year because they do well in moderate cold.

The earliest that you can plant centaurea in Watertown 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 grow to maturity. You can get started a few weeks earlier by starting your centaurea indoors.

Last Frost Date

The average date of last frost is April 15 in Watertown. You can expect an average low temperature of -20°F in the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Watertown and it will vary from year to year. Since half of the time in Watertown you get a frost after April 15 be ready to protect your centaurea in the event of a surprise late frost.

USDA Zone Info for Watertown

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 Watertown

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