Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In San Marcos you can determine when you can plant iceberg lettuce by referring to 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 slightly earlier in the year because they do ok in moderate cold.

The earliest that you can plant iceberg lettuce in San Marcos 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 fully mature. You can get started a few weeks earlier by starting your iceberg lettuce indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in San Marcos. You can expect an average low temperature of 30°F in the coldest months of winter.

Remember that USDA zone info for San Marcos may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in San Marcos it frosts late in the year after January 31 be ready to protect your iceberg lettuce if you have a surprise late frost.

USDA Zone Info for San Marcos

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 Marcos

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