When to Plant Romaine lettuce in Hercules, CA

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.

You should be able to determine when it's the best time to plant romaine lettuce by reviewing the USDA zone info for Hercules.


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 earlier in the year because they are very cold tolerant.

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 Hercules 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 fully mature. Starting your romaine lettuce indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Hercules the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Hercules is just an average and the actual date of last frost is different every year. Half of the time in Hercules it frosts late in the year after February 15 so make sure that you are ready to cover your romaine lettuce if you have a surprise late frost.

USDA Zone Info for Hercules

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 Hercules

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