The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to determine when you can plant nasturtium by checking out the USDA zone info for Janesville.

Planting Calendar for Nasturtium

Frost tolerance for nasturtium:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since nasturtium do not do well in cold weather you must wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant nasturtium in Janesville is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant nasturtium and expect a good harvest is probably August. Any later than that and your nasturtium may not have a chance to grow to maturity. Starting your nasturtium indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Janesville. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Janesville may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Janesville last frost occurs after April 15 be ready to protect your nasturtium if you have a late frost.

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.