One of the best tools that you have as gardeners to help us estimate 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.

In Bethalto you can determine when it's possible to plant oenothera by reviewing 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.

Since oenothera do well in moderate cold you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant oenothera in Bethalto 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 fully mature. Starting your oenothera indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Bethalto. You should expect an average low temperature of -10°F in the coldest months of winter.

Always keep in mind that USDA zone info for Bethalto is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Bethalto it frosts late in the year after April 15 so always be ready to cover your oenothera if you have a late frost.

USDA Zone Info for Bethalto

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Bethalto

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