One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of getting a good idea when to plant oenothera is to refer to the USDA zone info for Lebanon.

Planting Calendar for Oenothera

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

Oenothera do well in mild cold which tells us that you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant oenothera in Lebanon 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

On average the last frost is on April 15 in Lebanon. You should expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Lebanon is an average the actual date of last frost changes from year to year. Since half of the time in Lebanon there is a last frost after April 15 be ready to cover your oenothera if you have a surprise late frost.

USDA Zone Info for Lebanon

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 Lebanon

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