One of the first steps you take when you are estimating 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.

In San Mateo you can determine when to plant iceberg lettuce by using the USDA zone info.

Planting Calendar for Iceberg lettuce

Frost tolerance for iceberg lettuce:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant iceberg lettuce just a tiny bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant iceberg lettuce in San Mateo is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant iceberg lettuce and expect a good harvest is probably September. If you wait any later than that and your iceberg lettuce may not have a chance to grow to maturity. If you are starting your iceberg lettuce indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on January 31 in San Mateo. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for San Mateo is not always accurate the actual date of last frost changes from year to year. Half of the time in San Mateo you get surprised by a frost after January 31 so always be ready to cover your iceberg lettuce if you have a surprise late frost.

USDA Zone Info for San Mateo

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 San Mateo

You may be interested in your other planting guides for San Mateo.