Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant violas in Lake Oswego should be determined by using the USDA zone info.

Planting Calendar for Violas

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

Violas can survive in cold weather which means that you can plant them earlier in the year than other frost tender plants.

The earliest that you can plant violas in Lake Oswego 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. If you wait any later than that and your violas may not have a chance to fully mature. You can get started a little bit earlier by starting your violas indoors.

Last Frost Date

The average date of last frost is March 15 in Lake Oswego. You should expect an average low temperature of 15°F in the coldest months of winter.

Remember that USDA zone info for Lake Oswego is just an average and the actual date of last frost changes from year to year. Since half of the time in Lake Oswego it frosts late in the year after March 15 be ready to cover your violas in the event of one of those late frosts.

USDA Zone Info for Lake Oswego

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Lake Oswego

You may be interested in your other planting guides for Lake Oswego.