The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By referring to the USDA zone info for Spring Grove you will be able to figure out when it's a good idea 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.

Oenothera do well in moderate cold which tells us that you can plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant oenothera in Spring Grove 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. You probably don't want to wait any later than that or else your oenothera may not have a chance to grow to maturity. Starting your oenothera indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Spring Grove. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Spring Grove is an average the actual date of last frost is different every year. Half of the time in Spring Grove you get surprised by a frost after April 15 so make sure that you are prepared to protect your oenothera if you have one of those late frosts.

USDA Zone Info for Spring Grove

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 Spring Grove

You may be interested in your other planting guides for Spring Grove.