The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. 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 figure out when it's possible to plant oenothera by looking at the USDA zone info for Oak Ridge.

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 just a bit earlier in the year than other frost tender plants.

The earliest that you can plant oenothera in Oak Ridge 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. You probably don't want to wait any later than that or else your oenothera may not have a chance to fully mature. If you are starting your oenothera indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Oak Ridge the average date of last frost happens on April 15. You can expect an average low temperature of 5°F in the coldest months of winter.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Oak Ridge and it can change quite a bit from year to year. Since half of the time in Oak Ridge last frost occurs after April 15 be ready to cover your oenothera if you have one of those late frosts.

USDA Zone Info for Oak Ridge

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Oak Ridge

You may be interested in your other planting guides for Oak Ridge.