One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of figuring out when it's possible to plant oenothera is to consult the USDA zone info for Plymouth.

Planting Calendar for Oenothera

Frost tolerance for oenothera:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Oenothera are moderately cold tolerant which means that you can get them planted earlier than more sensitive plants.

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

Last Frost Date

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

Since the USDA zone info for Plymouth is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Plymouth you get a frost after April 15 be ready to cover your oenothera if you have a surprise late frost.

USDA Zone Info for Plymouth

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Plymouth

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