Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Portsmouth you can estimate when it's the best time to plant amaranthus by looking at the USDA zone info.

Planting Calendar for Amaranthus

Frost tolerance for amaranthus:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Amaranthus require warm weather which tells us that it's necessary to wait until it warms up after the last frost has passed before you can plant them.

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

Last Frost Date

In Portsmouth the average date of last frost happens on April 15. It might get as low as -5°F during the coldest months of winter.

Keep in mind that USDA zone info for Portsmouth is an average and the actual date of last frost changes from year to year. Since half of the time in Portsmouth it frosts late in the year after April 15 be ready to cover your amaranthus in the event of a surprise late frost.

USDA Zone Info for Portsmouth

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 Portsmouth

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