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.

In Madison you can figure out when to plant nierembergia by reviewing the USDA zone info.

Planting Calendar for Nierembergia

Frost tolerance for nierembergia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since nierembergia do not do well in cold weather you really should wait until after the last frost when the weather gets warmer before you can plant them.

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

The last month that you can plant nierembergia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your nierembergia may not have a chance to fully mature. Starting your nierembergia indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Madison the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Madison is not always accurate the actual date of last frost will vary from year to year. Half of the time in Madison last frost occurs after May 15 so always be ready to cover your nierembergia if you have a surprise late frost.

USDA Zone Info for Madison

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Madison

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