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.

It's a good idea to determine when you can plant anchusa by looking at the USDA zone info for Portsmouth.

Planting Calendar for Anchusa

Frost tolerance for anchusa:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since anchusa are one of those plants that can tolerate quite a bit of cold weather you can plant them much earlier in the year than other plants that might not handle the cold.

The earliest that you can plant anchusa 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 anchusa and expect a good harvest is probably September. If you wait any later than that and your anchusa may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your anchusa indoors.

Last Frost Date

On average the last frost is on April 15 in Portsmouth. In the coldest months of winter you should expect an average low temperature of -5°F.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Portsmouth and it will vary from year to year. Half of the time in Portsmouth it frosts late in the year after April 15 so make sure that you are ready to cover your anchusa 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.