One of the first steps you take when you are getting a good idea 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.

A common way of figuring out when it's a good idea to plant celeriac is to examine the USDA zone info for Umatilla.

Planting Calendar for Celeriac

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

Since celeriac are moderately cold tolerant you can plant them just a bit earlier in the year than more sensitive plants.

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

Last Frost Date

In Umatilla the average date of last frost happens on April 15. It might get as low as 5°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Umatilla and it will vary from year to year. Since half of the time in Umatilla there is a last frost after April 15 be ready to protect your celeriac in the event of a late frost.

USDA Zone Info for Umatilla

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Umatilla

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