The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to estimate when you can plant mustard greens by looking at the USDA zone info for Roma.

Planting Calendar for Mustard greens

Frost tolerance for mustard greens:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since mustard greens do well in moderate cold you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant mustard greens in Roma is January. However, you really should wait until February if you don't want to take any chances.

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

Last Frost Date

The average date of last frost is February 15 in Roma. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for Roma is not always accurate the actual date of last frost will vary from year to year. Half of the time in Roma you get a frost after February 15 so make sure that you are prepared to protect your mustard greens in the event of a 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.