One of the best tools that you have as gardeners to help us determine 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 Oregon you will be able to determine when it's possible 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.

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 Oregon 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. Any later than that and your violas may not have a chance to really do well. 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

The average date of last frost is April 15 in Oregon. In the coldest months of winter you should expect an average low temperature of -5°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Oregon and it changes from year to year. Since half of the time in Oregon it frosts late in the year after April 15 be ready to protect your violas in the event of a late frost.

USDA Zone Info for Oregon

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Oregon

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