Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By checking out the USDA zone info for Portland it's a good idea to estimate when you can plant celeriac.

Planting Calendar for Celeriac

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

You can plant celeriac a bit earlier in the year because they do well in moderate cold.

The earliest that you can plant celeriac in Portland 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 celeriac and expect a good harvest is probably October. Any later than that and your celeriac may not have a chance to fully mature. Starting your celeriac indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Portland the average date of last frost happens on February 15. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Portland is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Portland you get surprised by a frost after February 15 be ready to cover your celeriac if you have one of those late frosts.

USDA Zone Info for Portland

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Portland

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