One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. 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 Denison should be read to figure out when it's the best time to 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 a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant oenothera in Denison 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 grow to maturity. 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 Denison. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Denison is an average the actual date of last frost is different every year. Since half of the time in Denison there is a last frost after April 15 be ready to protect your oenothera if you have a surprise late frost.

USDA Zone Info for Denison

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 Denison

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