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.

By using the USDA zone info for Plymouth it's possible to figure out when you can plant erysimum.

Planting Calendar for Erysimum

Frost tolerance for erysimum:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since erysimum do well in moderate cold you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant erysimum 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 erysimum and expect a good harvest is probably September. If you wait any later than that and your erysimum may not have a chance to really do well. If you are starting your erysimum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Plymouth is not always accurate the actual date of last frost is different every year. Since half of the time in Plymouth there is a last frost after April 15 be ready to cover your erysimum in the event of 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.