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.

You should be able to estimate when to plant oenothera by checking out the USDA zone info for Mill Creek.

Planting Calendar for Oenothera

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

Oenothera are moderately cold tolerant which means that you can plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant oenothera in Mill Creek 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. You can get started a few weeks earlier by starting your oenothera indoors.

Last Frost Date

On average all chance of frost has passed is on March 15 in Mill Creek. It might get as low as 15°F during the coldest months of winter.

Remember that USDA zone info for Mill Creek is an average and the actual date of last frost changes from year to year. Since half of the time in Mill Creek you get surprised by a frost after March 15 be ready to cover your oenothera in the event of a surprise late frost.

USDA Zone Info for Mill Creek

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 Mill Creek

You may be interested in your other planting guides for Mill Creek.