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.

By checking out the USDA zone info for Coralville it's a good idea to estimate when it's a good idea to plant violets.

Planting Calendar for Violets

Frost tolerance for violets:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Violets tend to make it in moderate cold which tells us that you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant violets in Coralville 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 violets and expect a good harvest is probably September. Any later than that and your violets may not have a chance to grow to maturity. If you are starting your violets indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Coralville. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Coralville is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Coralville last frost occurs after April 15 be ready to protect your violets in the event of a surprise late frost.

USDA Zone Info for Coralville

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 Coralville

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