One of the best tools that you have as gardeners to help us estimate 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.

The USDA zone info for Plymouth can be reviewed to estimate when to plant impatiens.

Planting Calendar for Impatiens

Frost tolerance for impatiens:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's a bad idea to plant impatiens until after the last frost because they are not cold tolerant.

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

The last month that you can plant impatiens and expect a good harvest is probably August. You probably don't want to wait any later than that or else your impatiens may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your impatiens 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.

Just be sure to remember that USDA zone info for Plymouth is just an average and the actual date of last frost will vary from year to year. Half of the time in Plymouth it frosts late in the year after April 15 so always be ready to cover your impatiens 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.