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.

The USDA zone info for Janesville can be read to determine when to plant potatos.

Planting Calendar for Potatos

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

Potatos do ok in cold weather which means that you can plant them much earlier in the year than more sensitive plants.

The earliest that you can plant potatos in Janesville 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 potatos and expect a good harvest is probably September. If you wait any later than that and your potatos may not have a chance to grow to maturity. Starting your potatos indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Janesville. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Janesville is an average the actual date of last frost will vary from year to year. Since half of the time in Janesville you get a frost after April 15 be ready to protect your potatos in the event of one of those late frosts.

USDA Zone Info for Janesville

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 Janesville

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