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.

The best time to plant browallia in Grinnell can be determined by checking out the USDA zone info.

Planting Calendar for Browallia

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

Browallia do not do well in cold weather which tells us that you need to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant browallia in Grinnell 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. If you wait any later than that and your browallia may not have a chance to grow to maturity. If you are starting your browallia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Grinnell. In the coldest months of winter you should expect an average low temperature of -20°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Grinnell and it can change quite a bit from year to year. Since half of the time in Grinnell there is a last frost after April 15 be ready to protect your browallia in the event of a late frost.

USDA Zone Info for Grinnell

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Grinnell

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