One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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 a good idea to estimate when it's a good idea to plant oenothera by looking at the USDA zone info for Pullman.

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 moderate cold which tells us that you can start planting them earlier than more sensitive plants.

The earliest that you can plant oenothera in Pullman 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 really do well. Starting your oenothera indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Pullman. It might get as low as -5°F during the coldest months of winter.

Remember that USDA zone info for Pullman is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Pullman there is a last frost after April 15 so always be ready to cover your oenothera in the event of one of those late frosts.

USDA Zone Info for Pullman

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°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 0°F.

Plants to Grow in Pullman

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