One of the best tools that you have as gardeners to help us figure out 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.

The best time to plant oenothera in Zone 2b should be determined by checking out the USDA zone info.

Planting Calendar for Oenothera

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

You can plant oenothera a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant oenothera in Zone 2b is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant oenothera and expect a good harvest is probably August. You probably don't want to wait any later than that or else your oenothera may not have a chance to really do well. You can get started a little bit earlier by starting your oenothera indoors.

Last Frost Date

In Zone 2b the average date of last frost happens on May 15. You should expect an average low temperature of -45°F in the coldest months of winter.

Since the USDA zone info for Zone 2b is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 2b you get surprised by a frost after May 15 be ready to cover your oenothera if you have a surprise late frost.

USDA Zone Info for Zone 2b

Here is the info for USDA Zone 2b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	August 15
Lowest Expected Low	-45°F
Highest Expected Low	-40°F

This means that on a really cold year, the coldest it will get is -45°F. On most years you should be prepared to experience lows near -40°F.

Plants to Grow in Zone 2b

You may be interested in your other planting guides for Zone 2b.