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.

The USDA zone info for Rio Vista can be used to estimate when it's a good idea to plant iceberg lettuce.

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.

Iceberg lettuce are one of those plants that can tolerate a tiny bit of cold weather which tells us that you can plant them slightly earlier than other frost tender plants.

The earliest that you can plant iceberg lettuce in Rio Vista 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. You probably don't want to wait any later than that or else your iceberg lettuce may not have a chance to really do well. Starting your iceberg lettuce indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Rio Vista. It might get as low as 25°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Rio Vista and it can change quite a bit from year to year. Half of the time in Rio Vista you get surprised by a frost after February 15 so make sure that you are prepared to protect your iceberg lettuce in the event of a late frost.

USDA Zone Info for Rio Vista

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Rio Vista

You may be interested in your other planting guides for Rio Vista.