One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of making a decision about when you can plant chrysanthemums is to look at the USDA zone info for Portsmouth.

Planting Calendar for Chrysanthemums

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

Chrysanthemums do ok in moderate cold which means that you can get them planted just a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant chrysanthemums 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 chrysanthemums and expect a good harvest is probably August. Any later than that and your chrysanthemums may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your chrysanthemums 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. Since half of the time in Portsmouth there is a last frost after April 15 be ready to cover your chrysanthemums if you have a surprise late frost.

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.