One of the best tools that you have as gardeners to help us estimate 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.

In Coralville you can determine when you can plant browallia by referring to the USDA zone info.

Planting Calendar for Browallia

Frost tolerance for browallia:	Not tolerant of frost.
When to plant:	After the last frost.

Browallia are not cold tolerant which tells us that it is necessary to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant browallia in Coralville is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant browallia and expect a good harvest is probably August. Any later than that and your browallia may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your browallia indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Coralville. You should expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Coralville is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Coralville there is a last frost after April 15 be ready to protect your browallia if you have a 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.