One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. 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 Altoona you should be able to determine when it's a good idea to plant browallia.

Planting Calendar for Browallia

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

Since browallia are not cold tolerant it is necessary to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant browallia in Altoona is May. However, you really should wait until June 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. You can get started a couple of weeks earlier by starting your browallia indoors.

Last Frost Date

On average the last frost is on May 15 in Altoona. You can expect an average low temperature of -25°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Altoona may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Altoona you get surprised by a frost after May 15 be ready to protect your browallia in the event of one of those late frosts.

USDA Zone Info for Altoona

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Altoona

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