One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

In Roma you can estimate when it's a good idea to plant sweet corn by looking at the USDA zone info.

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.

You can plant sweet corn slightly earlier in the year because they do ok in moderate cold.

The earliest that you can plant sweet corn in Roma 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 grow to maturity. Starting your sweet corn 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 Roma. In the coldest months of winter you should expect an average low temperature of 25°F.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Roma and it can change quite a bit from year to year. Since half of the time in Roma there is a last frost after February 15 be ready to cover your sweet corn if you have a surprise late frost.

USDA Zone Info for Roma

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 Roma

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