Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of figuring out when it's possible to plant oenothera is to consult the USDA zone info for Sun Prairie.

Planting Calendar for Oenothera

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

Oenothera do well in moderate cold which means that you can plant them earlier than other frost tender plants.

The earliest that you can plant oenothera in Sun Prairie 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 oenothera and expect a good harvest is probably September. If you wait any later than that and your oenothera may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your oenothera indoors.

Last Frost Date

The average date of last frost is April 15 in Sun Prairie. You should expect an average low temperature of -20°F in the coldest months of winter.

Always keep in mind that USDA zone info for Sun Prairie is just an average and the actual date of last frost changes from year to year. Half of the time in Sun Prairie last frost occurs after April 15 so just be sure to be ready to protect your oenothera if you have a late frost.

USDA Zone Info for Sun Prairie

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 Sun Prairie

You may be interested in your other planting guides for Sun Prairie.