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

You can determine when it's possible to plant dianthus in Portsmouth by using the USDA zone info.

Planting Calendar for Dianthus

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

You can plant dianthus just a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant dianthus 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 dianthus and expect a good harvest is probably September. Any later than that and your dianthus may not have a chance to fully mature. You can get started a little bit earlier by starting your dianthus indoors.

Last Frost Date

In Portsmouth the average date of last frost happens on March 15. In the coldest months of winter you can expect an average low temperature of 10°F.

Keep in mind that USDA zone info for Portsmouth is an average and the actual date of last frost is different every year. Since half of the time in Portsmouth there is a last frost after March 15 be ready to cover your dianthus if you have a surprise late frost.

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.