One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of determining when it's the best time to plant oenothera is to look at the USDA zone info for Calexico.

Planting Calendar for Oenothera

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

Since oenothera are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant oenothera in Calexico 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. If you are starting your oenothera indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Calexico the average date of last frost happens on January 31. You can expect an average low temperature of 30°F in the coldest months of winter.

Keep in mind that USDA zone info for Calexico is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Calexico it frosts late in the year after January 31 be ready to protect your oenothera if you have a surprise late frost.

USDA Zone Info for Calexico

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Calexico

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