One of the first steps you take when you are determining your gardening schedule is find your 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.

The USDA zone info for Lewiston can be used to estimate when to plant violas.

Planting Calendar for Violas

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

Violas do well in cold which tells us that you can start planting them much earlier than other frost tender plants.

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

The last month that you can plant violas and expect a good harvest is probably September. You probably don't want to wait any later than that or else your violas may not have a chance to really do well. You can get started a few weeks earlier by starting your violas indoors.

Last Frost Date

In Lewiston the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Remember that USDA zone info for Lewiston may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Lewiston last frost occurs after April 15 so be sure to be ready to cover your violas if you have a surprise late frost.

USDA Zone Info for Lewiston

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 Lewiston

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