Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Westminster you can determine when it's the best time to plant oenothera 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.

Oenothera tend to make it in moderate cold which tells us that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant oenothera in Westminster 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 really do well. If you are starting your oenothera indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Westminster the average date of last frost happens on January 31. You should expect an average low temperature of 35°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Westminster and it will vary from year to year. Half of the time in Westminster you get surprised by a frost after January 31 so be sure to be ready to protect your oenothera if you have a surprise late frost.

USDA Zone Info for Westminster

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in Westminster

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