One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. 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 Altoona can be read to figure out when it's possible to plant hollyhocks.

Planting Calendar for Hollyhocks

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

You can plant hollyhocks a little bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant hollyhocks 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 hollyhocks and expect a good harvest is probably August. You probably don't want to wait any later than that or else your hollyhocks may not have a chance to fully mature. You can get started a little bit earlier by starting your hollyhocks indoors.

Last Frost Date

On average the last frost is on 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 can change quite a bit from year to year. Half of the time in Altoona there is a last frost after May 15 so just be sure to be ready to cover your hollyhocks 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.