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.

By checking out the USDA zone info for Rialto it's a good idea to figure out when it's possible to plant lettuce.

Planting Calendar for Lettuce

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

Lettuce do ok in mild cold which tells us that you can plant them a bit earlier in the year than other plants that might not handle the cold.

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

Last Frost Date

In Rialto the average date of last frost happens on January 31. It might get as low as 30°F during the coldest months of winter.

Remember that USDA zone info for Rialto is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Rialto you get surprised by a frost after January 31 so always be ready to protect your lettuce in the event of one of those late frosts.

USDA Zone Info for Rialto

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 Rialto

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