Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. 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 Williamsport can be used to determine when you can plant oenothera.

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 Williamsport 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. If you wait 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 little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Williamsport. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Williamsport may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Williamsport last frost occurs after April 15 so be sure to be ready to cover your oenothera in the event of a surprise late frost.

USDA Zone Info for Williamsport

Here is the info for USDA Zone 6b.

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

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

Plants to Grow in Williamsport

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