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

In Westminster you can figure out when you can plant oenothera 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.

Oenothera do well in moderate cold which tells us that you can plant them a little bit earlier than other plants that might not handle the cold.

The earliest that you can plant oenothera in Westminster 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. If you are starting your oenothera indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Westminster. In the coldest months of winter you can expect an average low temperature of 0°F.

Since the USDA zone info for Westminster is just an average the actual date of last frost will vary from year to year. Half of the time in Westminster last frost occurs after April 15 so just be sure to be ready to cover your oenothera if you have a surprise late frost.

USDA Zone Info for Westminster

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 Westminster

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