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

The first opportunity to plant strawflowers in Portsmouth should be determined by using the USDA zone info.

Planting Calendar for Strawflowers

Frost tolerance for strawflowers:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Strawflowers are one of those plants that can tolerate a tiny bit of cold weather which tells us that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant strawflowers in Portsmouth is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant strawflowers and expect a good harvest is probably August. Any later than that and your strawflowers may not have a chance to really do well. Starting your strawflowers indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Remember that USDA zone info for Portsmouth is not always accurate and the actual date of last frost can change quite a bit 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 strawflowers in the event of 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.