The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of getting a good idea when you can plant anchusa is to examine the USDA zone info for Riverside.

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 earlier in the year than more sensitive plants.

The earliest that you can plant anchusa in Riverside 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. You probably don't want to wait any later than that or else your anchusa may not have a chance to fully mature. You can get started a few weeks earlier by starting your anchusa indoors.

Last Frost Date

The average date of last frost is April 15 in Riverside. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Riverside may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Riverside there is a last frost after April 15 be ready to protect your anchusa if you have one of those late frosts.

USDA Zone Info for Riverside

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 Riverside

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