One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Northfield it's possible to estimate when it's possible to plant anchusa.

Planting Calendar for Anchusa

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

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

The earliest that you can plant anchusa in Northfield 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 anchusa and expect a good harvest is probably August. Any later than that and your anchusa may not have a chance to grow to maturity. If you are starting your anchusa indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Northfield. In the coldest months of winter you can expect an average low temperature of -25°F.

Keep in mind that USDA zone info for Northfield is just an average and the actual date of last frost will vary from year to year. Since half of the time in Northfield you get surprised by a frost after May 15 be ready to cover your anchusa if you have a late frost.

USDA Zone Info for Northfield

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Northfield

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