One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of determining when it's a good idea to plant mustard greens is to consult the USDA zone info for San Marino.

Planting Calendar for Mustard greens

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

Mustard greens tend to make it in a little bit of cold which means that you can plant them just a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant mustard greens in San Marino 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. If you wait any later than that and your mustard greens may not have a chance to grow to maturity. Starting your mustard greens indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is January 31 in San Marino. You can expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for San Marino is an average the actual date of last frost will vary from year to year. Half of the time in San Marino you get surprised by a frost after January 31 so always be ready to cover your mustard greens if you have a surprise late frost.

USDA Zone Info for San Marino

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 Marino

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