When to Plant Romaine lettuce in Napa, CA

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

The earliest that you can plant romaine lettuce in Napa should be estimated by checking out the USDA zone info.


Planting Calendar for Romaine lettuce

Frost tolerance for romaine lettuce: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

You can plant romaine lettuce quite a bit earlier in the year because they do well in cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant romaine lettuce
Possibly ok, but a risky time to plant romaine lettuce
Probably not a good time to plant romaine lettuce

The earliest that you can plant romaine lettuce in Napa 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 romaine lettuce and expect a good harvest is probably October. Any later than that and your romaine lettuce may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your romaine lettuce indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Napa. You should expect an average low temperature of 25°F in the coldest months of winter.

Remember that USDA zone info for Napa is just an average and the actual date of last frost will vary from year to year. Half of the time in Napa you get a frost after February 15 so make sure that you are ready to cover your romaine lettuce if you have a late frost.

USDA Zone Info for Napa

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 Low25°F
Highest Expected Low30°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 Napa

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