The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant bittercress in Oregon can be determined by reviewing the USDA zone info.

Planting Calendar for Bittercress

Frost tolerance for bittercress:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Bittercress are barely cold tolerant which means that you can start planting them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant bittercress in Oregon 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 bittercress and expect a good harvest is probably August. You probably don't want to wait any later than that or else your bittercress may not have a chance to fully mature. You can get started a little bit earlier by starting your bittercress indoors.

Last Frost Date

In Oregon the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -20°F.

Remember that USDA zone info for Oregon 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 Oregon last frost occurs after April 15 so make sure that you are prepared to cover your bittercress if you have a surprise late frost.

USDA Zone Info for Oregon

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Oregon

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