When to Plant Oenothera in Onalaska, WI

One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant oenothera in Onalaska can be figured out by looking at 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 bit earlier in the year because they are moderately cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant oenothera
Possibly ok, but a risky time to plant oenothera
Probably not a good time to plant oenothera

The earliest that you can plant oenothera in Onalaska 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 grow to maturity. Starting your oenothera indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Remember that USDA zone info for Onalaska is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Onalaska you get surprised by a frost after May 15 be ready to cover your oenothera in the event of one of those late frosts.

USDA Zone Info for Onalaska

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 Onalaska

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