One of the first steps you take when you are determining 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.

The earliest that you can plant radishes in Oregon should be estimated by reviewing the USDA zone info.

Planting Calendar for Radishes

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

Radishes tend to make it in a bit of cold which tells us that you can plant them much earlier in the year than other frost tender plants.

The earliest that you can plant radishes in Oregon 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 radishes and expect a good harvest is probably September. You probably don't want to wait any later than that or else your radishes may not have a chance to fully mature. Starting your radishes indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Oregon. You should expect an average low temperature of -20°F in the coldest months of winter.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Oregon and it can change quite a bit from year to year. Half of the time in Oregon you get surprised by a frost after April 15 so make sure that you are prepared to cover your radishes if you have a late frost.

USDA Zone Info for Oregon

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°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 -15°F.

Plants to Grow in Oregon

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