The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Hiawatha can be looked at to estimate when you can plant oenothera.

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 just a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant oenothera in Hiawatha 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 grow to maturity. You can get started a few weeks earlier by starting your oenothera indoors.

Last Frost Date

In Hiawatha the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Hiawatha is an average the actual date of last frost changes from year to year. Half of the time in Hiawatha there is a last frost after April 15 so make sure that you are ready to cover your oenothera if you have a late frost.

USDA Zone Info for Hiawatha

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 Hiawatha

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