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.

You can figure out when it's possible to plant oenothera in Madison by referring to the USDA zone info.

Planting Calendar for Oenothera

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

You can plant oenothera a little bit earlier in the year because they do well in moderate cold.

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

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

Last Frost Date

The average date of last frost is May 15 in Madison. In the coldest months of winter you can expect an average low temperature of -25°F.

Since the USDA zone info for Madison 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 Madison there is a last frost after May 15 be ready to protect your oenothera if you have a 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.