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.

A way of getting a good idea when it's possible to plant oenothera is to look at the USDA zone info for Waupun.

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 tells us that you can plant them earlier than other frost tender plants.

The earliest that you can plant oenothera in Waupun 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. Any later than that and 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 April 15 in Waupun. In the coldest months of winter you can expect an average low temperature of -20°F.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Waupun and it changes from year to year. Since half of the time in Waupun it frosts late in the year after April 15 be ready to cover your oenothera in the event of one of those late frosts.

USDA Zone Info for Waupun

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 Waupun

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