One of the first steps you take when you are making a decision about 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.

You can estimate when you can plant purple rock cress in San Bruno by reviewing the USDA zone info.

Planting Calendar for Purple Rock Cress

Frost tolerance for purple rock cress:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

You can plant purple rock cress a lot earlier in the year because they are very cold tolerant.

The earliest that you can plant purple rock cress in San Bruno 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 purple rock cress and expect a good harvest is probably October. You probably don't want to wait any later than that or else your purple rock cress may not have a chance to fully mature. You can get started a little bit earlier by starting your purple rock cress indoors.

Last Frost Date

On average the last frost is on January 31 in San Bruno. In the coldest months of winter you should expect an average low temperature of 30°F.

Since the USDA zone info for San Bruno is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in San Bruno there is a last frost after January 31 so make sure that you are prepared to protect your purple rock cress if you have a surprise late frost.

USDA Zone Info for San Bruno

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 Bruno

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