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 USDA zone info for Silvis should be reviewed to figure out 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.

Celeriac can survive in mild cold which means that you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant celeriac in Silvis 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 fully mature. If you are starting your celeriac indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Silvis the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Silvis is just an average the actual date of last frost changes from year to year. Half of the time in Silvis there is a last frost after April 15 so make sure that you are ready to protect your celeriac in the event of a late frost.

USDA Zone Info for Silvis

Here is the info for USDA Zone 5b.

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

Plants to Grow in Silvis

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