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

The first opportunity to plant black radish in Phoenix should be estimated by looking at the USDA zone info.

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 do well in moderate cold which tells us that you can plant them earlier than other plants that might not handle the cold.

The earliest that you can plant black radish in Phoenix is February. However, you really should wait until March 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 September. If you wait any later than that and your black radish may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your black radish indoors.

Last Frost Date

The average date of last frost is March 15 in Phoenix. It might get as low as 10°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Phoenix and it is different every year. Since half of the time in Phoenix last frost occurs after March 15 be ready to protect your black radish if you have one of those late frosts.

USDA Zone Info for Phoenix

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Phoenix

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