Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Oroville you should be able to estimate when it's possible to plant oenothera.

Planting Calendar for Oenothera

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

Oenothera are one of those plants that can tolerate a little bit of cold weather which means that you can plant them earlier than other frost tender plants.

The earliest that you can plant oenothera in Oroville is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant oenothera and expect a good harvest is probably October. If you wait any later than that and your oenothera may not have a chance to fully mature. You can get started a little bit earlier by starting your oenothera indoors.

Last Frost Date

In Oroville the average date of last frost happens on February 15. You should expect an average low temperature of 25°F in the coldest months of winter.

Remember that USDA zone info for Oroville may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Oroville last frost occurs after February 15 be ready to cover your oenothera if you have a late frost.

USDA Zone Info for Oroville

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Oroville

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