One of the first steps you take when you are figuring out your gardening schedule is find your 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.

You can figure out when it's a good idea to plant black radish in Seattle by checking out 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.

Since black radish are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant black radish in Seattle 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. You probably don't want to wait any later than that or else your black radish may not have a chance to grow to maturity. You can get started a little bit earlier by starting your black radish indoors.

Last Frost Date

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

Since the USDA zone info for Seattle is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Seattle there is a last frost after March 15 be ready to protect your black radish in the event of a late frost.

USDA Zone Info for Seattle

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Seattle

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