One of the first steps you take when you are making a decision about 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.

You should be able to figure out when to plant oenothera by referring to the USDA zone info for Calistoga.

Planting Calendar for Oenothera

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

Oenothera do ok in mild cold which tells us that you can plant them a little bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant oenothera in Calistoga 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. You probably don't want to wait any later than that or else your oenothera may not have a chance to grow to maturity. Starting your oenothera indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on February 15 in Calistoga. You can expect an average low temperature of 20°F in the coldest months of winter.

Keep in mind that USDA zone info for Calistoga may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Calistoga it frosts late in the year after February 15 so always be ready to protect your oenothera in the event of one of those late frosts.

USDA Zone Info for Calistoga

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Calistoga

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