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

It's a good idea to estimate when you can plant violas by using the USDA zone info for Altoona.

Planting Calendar for Violas

Frost tolerance for violas:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since violas do well in cold you can plant them quite a bit earlier in the year than other frost tender plants.

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

The last month that you can plant violas and expect a good harvest is probably August. Any later than that and your violas may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your violas indoors.

Last Frost Date

In Altoona the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -25°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Altoona and it can change quite a bit from year to year. Half of the time in Altoona you get surprised by a frost after May 15 so be sure to be ready to cover your violas 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.