Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. 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 the best time to plant radishes is to use the USDA zone info for San Bruno.

Planting Calendar for Radishes

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

Radishes do well in cold weather which tells us that you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant radishes 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 radishes and expect a good harvest is probably October. You probably don't want to wait any later than that or else your radishes may not have a chance to really do well. You can get started a little bit earlier by starting your radishes indoors.

Last Frost Date

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

Since the USDA zone info for San Bruno may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in San Bruno you get a frost after January 31 so just be sure to be ready to cover your radishes in the event of one of those late frosts.

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.