The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when it's possible to plant iberis in Altoona by referring to the USDA zone info.

Planting Calendar for Iberis

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

Iberis are moderately cold tolerant which tells us that you can start planting them earlier than more sensitive plants.

The earliest that you can plant iberis 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 iberis and expect a good harvest is probably August. Any later than that and your iberis may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your iberis indoors.

Last Frost Date

The average date of last frost is May 15 in Altoona. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Altoona is just an average 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 ready to cover your iberis if you have 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.