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.

The first chance to plant centaurea in Plymouth can be figured out 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.

Since centaurea are moderately cold tolerant you can plant them a little earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant centaurea in Plymouth 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 Plymouth. It might get as low as -15°F during the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Plymouth and it is different every year. Half of the time in Plymouth it frosts late in the year after April 15 so always be ready to cover your centaurea if you have one of those late frosts.

USDA Zone Info for Plymouth

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 Plymouth

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