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.

By checking out the USDA zone info for Oskaloosa you will be able to determine when 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.

Hollyhocks tend to make it in mild cold which means that you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant hollyhocks in Oskaloosa 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 hollyhocks and expect a good harvest is probably September. If you wait any later than that and your hollyhocks may not have a chance to really do well. You can get started a few weeks earlier by starting your hollyhocks indoors.

Last Frost Date

On average the last frost is on April 15 in Oskaloosa. In the coldest months of winter you can expect an average low temperature of -15°F.

Remember that USDA zone info for Oskaloosa is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Oskaloosa last frost occurs after April 15 so be sure to be ready to protect your hollyhocks in the event of a late frost.

USDA Zone Info for Oskaloosa

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 Oskaloosa

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