The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Portsmouth you should be able to determine when it's the best time to plant kale.

Planting Calendar for Kale

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

You can plant kale a little bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant kale in Portsmouth 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 kale and expect a good harvest is probably September. Any later than that and your kale may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your kale indoors.

Last Frost Date

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

Since the USDA zone info for Portsmouth may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Portsmouth there is a last frost after April 15 so be sure to be ready to cover your kale if you have one of those late frosts.

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.