When to Plant Romaine lettuce in Upland, CA

One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Upland you should be able to determine when it's possible to plant romaine lettuce.


Planting Calendar for Romaine lettuce

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

Romaine lettuce tend to make it in a bit of cold which means that you can plant them much earlier in the year than plants that are more sensitive to the 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 Upland 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. You probably don't want to wait any later than that or else your romaine lettuce may not have a chance to grow to maturity. You can get started a little bit earlier by starting your romaine lettuce indoors.

Last Frost Date

The average date of last frost is January 31 in Upland. You should expect an average low temperature of 30°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Upland 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 Upland last frost occurs after January 31 so just be sure to be ready to protect your romaine lettuce if you have a surprise late frost.

USDA Zone Info for Upland

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 Low30°F
Highest Expected Low35°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 Upland

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