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.

A way of making a decision about when it's possible to plant celeriac is to consult the USDA zone info for Harvard.

Planting Calendar for Celeriac

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

Celeriac do well in moderate cold which means that you can start planting them earlier than other frost tender plants.

The earliest that you can plant celeriac in Harvard 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. If you wait 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

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

Always keep in mind that USDA zone info for Harvard may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Harvard there is a last frost after April 15 be ready to cover your celeriac if you have one of those late frosts.

USDA Zone Info for Harvard

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 Harvard

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