One of the first steps you take when you are determining your gardening schedule is find your 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 it's a good idea to plant oenothera is to use the USDA zone info for Riverbank.

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 get them planted earlier than other plants that might not handle the cold.

The earliest that you can plant oenothera in Riverbank 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 grow to maturity. Starting your oenothera indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Riverbank. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for Riverbank is not always accurate the actual date of last frost will vary from year to year. Half of the time in Riverbank there is a last frost after February 15 so be sure to be ready to protect your oenothera in the event of a late frost.

USDA Zone Info for Riverbank

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 Riverbank

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