Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Pierre it's a good idea to estimate when you can plant violas.

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 plants that might not handle the cold.

The earliest that you can plant violas in Pierre 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 fully mature. If you are starting your violas indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Pierre. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Pierre is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Pierre you get surprised by a frost after May 15 be ready to protect your violas if you have a surprise late frost.

USDA Zone Info for Pierre

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 Pierre

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