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

In Boston you can estimate when to plant scarlet pimpernels by looking at the USDA zone info.

Planting Calendar for Scarlet Pimpernels

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

Since scarlet pimpernels do ok in moderate cold you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant scarlet pimpernels in Boston 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 scarlet pimpernels and expect a good harvest is probably August. If you wait any later than that and your scarlet pimpernels may not have a chance to fully mature. Starting your scarlet pimpernels indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Boston. In the coldest months of winter you should expect an average low temperature of -5°F.

Keep in mind that USDA zone info for Boston is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Boston you get a frost after April 15 so be sure to be ready to cover your scarlet pimpernels in the event of one of those late frosts.

USDA Zone Info for Boston

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Boston

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