One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

In Plymouth you can figure out when it's possible to plant petunias by looking at the USDA zone info.

Planting Calendar for Petunias

Frost tolerance for petunias:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Petunias tend to make it in mild cold which means that you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant petunias in Plymouth is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant petunias and expect a good harvest is probably August. You probably don't want to wait any later than that or else your petunias may not have a chance to fully mature. If you are starting your petunias indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Plymouth the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Keep in mind that USDA zone info for Plymouth may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Plymouth there is a last frost after April 15 so make sure that you are prepared to cover your petunias if you have a late frost.

USDA Zone Info for Plymouth

Here is the info for USDA Zone 6a.

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

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

Plants to Grow in Plymouth

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