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

The earliest that you can plant bittercress in Portland should be figured out by checking out 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.

You can plant bittercress just a tiny bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant bittercress in Portland 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. If you wait any later than that and your bittercress may not have a chance to really do well. You can get started a couple of weeks earlier by starting your bittercress indoors.

Last Frost Date

On average the last frost has passed is on March 15 in Portland. It might get as low as 15°F during the coldest months of winter.

Remember that USDA zone info for Portland is just an average and the actual date of last frost will vary from year to year. Half of the time in Portland last frost occurs after March 15 so just be sure to be ready to cover your bittercress in the event of a late frost.

USDA Zone Info for Portland

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 Portland

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