One of the first steps you take when you are making a decision about your gardening schedule is find your 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.

You will be able to determine when it's possible to plant sweet corn by referring to the USDA zone info for San Bernardino.

Planting Calendar for Sweet corn

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

Sweet corn do well in mild cold which means that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant sweet corn in San Bernardino 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 sweet corn and expect a good harvest is probably September. If you wait any later than that and your sweet corn may not have a chance to really do well. If you are starting your sweet corn indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for San Bernardino is not always accurate the actual date of last frost changes from year to year. Since half of the time in San Bernardino it frosts late in the year after February 15 be ready to cover your sweet corn in the event of one of those late frosts.

USDA Zone Info for San Bernardino

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 San Bernardino

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