Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By checking out the USDA zone info for Portsmouth it's a good idea to figure out when you can plant heliotrope.

Planting Calendar for Heliotrope

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

Since heliotrope do not do well in cold weather it's important to wait until after the last frost when the weather gets warmer before you can plant them.

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

Last Frost Date

In Portsmouth the average date of last frost happens on March 15. It might get as low as 10°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Portsmouth is not always accurate and the actual date of last frost changes from year to year. Half of the time in Portsmouth last frost occurs after March 15 so be sure to be ready to protect your heliotrope in the event of one of those late frosts.

USDA Zone Info for Portsmouth

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Portsmouth

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