One of the best tools that you have as gardeners to help us determine 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.

By using the USDA zone info for Pasadena you should be able to determine when it's possible to plant black radish.

Planting Calendar for Black radish

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

Black radish can survive in moderate cold which means that you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant black radish in Pasadena 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 black radish and expect a good harvest is probably October. Any later than that and your black radish may not have a chance to grow to maturity. Starting your black radish indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Pasadena the average date of last frost happens on February 15. You should expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Pasadena is just an average the actual date of last frost changes from year to year. Half of the time in Pasadena you get surprised by a frost after February 15 so be sure to be ready to protect your black radish if you have a surprise late frost.

USDA Zone Info for Pasadena

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Pasadena

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