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

It's possible to determine when it's a good idea to plant balsam by referring to the USDA zone info for Portsmouth.

Planting Calendar for Balsam

Frost tolerance for balsam:	Not tolerant of frost.
When to plant:	After the last frost.

It's probably not a good idea to plant balsam until after all chance of frost has passed because they require warm weather.

The earliest that you can plant balsam in Portsmouth 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 balsam and expect a good harvest is probably August. Any later than that and your balsam may not have a chance to really do well. You can get started a little bit earlier by starting your balsam indoors.

Last Frost Date

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

Since the USDA zone info for Portsmouth may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Portsmouth there is a last frost after April 15 be ready to cover your balsam if you have a late frost.

USDA Zone Info for Portsmouth

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 Portsmouth

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