Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of figuring out when it's possible to plant anchusa is to refer to the USDA zone info for Rock Falls.

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 quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant anchusa in Rock Falls 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. Starting your anchusa indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Rock Falls. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Rock Falls may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Rock Falls you get surprised by a frost after April 15 so be sure to be ready to cover your anchusa in the event of a late frost.

USDA Zone Info for Rock Falls

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Rock Falls

You may be interested in your other planting guides for Rock Falls.