The USDA Zone info is a great tool for gardeners to help us determine 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.

The first chance to plant oenothera in Altoona should be figured out by using 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 means that you can plant them a little bit earlier than more sensitive plants.

The earliest that you can plant oenothera in Altoona is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant oenothera and expect a good harvest is probably August. If you wait any later than that and 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

The average date of last frost is May 15 in Altoona. You should expect an average low temperature of -25°F in the coldest months of winter.

Always keep in mind that USDA zone info for Altoona is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Altoona there is a last frost after May 15 so make sure that you are prepared to protect your oenothera in the event of a surprise late frost.

USDA Zone Info for Altoona

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Altoona

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