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.

A way of making a decision about when it's the best time to plant oenothera is to look at the USDA zone info for Ambler.

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 some cold which tells us that you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant oenothera in Ambler 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 Ambler the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 0°F.

It's important to remember that USDA zone info for Ambler is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Ambler you get a frost after April 15 so just be sure to be ready to protect your oenothera in the event of a surprise late frost.

USDA Zone Info for Ambler

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 Ambler

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