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

In Siloam Springs you can figure out when to plant oenothera by using 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 are one of those plants that can tolerate a little bit of cold weather you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant oenothera in Siloam Springs 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. 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 little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Siloam Springs. In the coldest months of winter you can expect an average low temperature of 0°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Siloam Springs and it changes from year to year. Half of the time in Siloam Springs you get a frost after April 15 so make sure that you are ready to protect your oenothera in the event of a late frost.

USDA Zone Info for Siloam Springs

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Siloam Springs

You may be interested in your other planting guides for Siloam Springs.