Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to determine when it's a good idea to plant romaine lettuce by reviewing the USDA zone info for Chino Hills.

Planting Calendar for Romaine lettuce

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

Since romaine lettuce are very cold tolerant you can plant them a lot earlier in the year than other frost tender plants.

The earliest that you can plant romaine lettuce in Chino Hills 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. If you wait 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 couple of weeks earlier.

Last Frost Date

On average the last frost is on January 31 in Chino Hills. In the coldest months of winter you should expect an average low temperature of 30°F.

Always keep in mind that USDA zone info for Chino Hills may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Chino Hills there is a last frost after January 31 so be sure to be ready to cover your romaine lettuce in the event of one of those late frosts.

USDA Zone Info for Chino Hills

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 Chino Hills

You may be interested in your other planting guides for Chino Hills.