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.

It's possible to determine when it's the best time to plant oenothera by referring to the USDA zone info for Salem.

Planting Calendar for Oenothera

Frost tolerance for oenothera:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since oenothera do well in moderate cold you can plant them a little earlier in the year than other plants that might not handle the cold.

The earliest that you can plant oenothera in Salem 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 oenothera and expect a good harvest is probably September. Any later than that and your oenothera may not have a chance to grow to maturity. If you are starting your oenothera indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on March 15 in Salem. You should expect an average low temperature of 15°F in the coldest months of winter.

Since the USDA zone info for Salem is an average the actual date of last frost will vary from year to year. Half of the time in Salem last frost occurs after March 15 so always be ready to protect your oenothera if you have a surprise late frost.

USDA Zone Info for Salem

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 Salem

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