One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By checking out the USDA zone info for Oskaloosa it's a good idea to figure out when it's the best time to plant hardy hibiscus.

Planting Calendar for Hardy Hibiscus

Frost tolerance for hardy hibiscus:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Hardy Hibiscus are one of those plants that can tolerate quite a bit of cold weather which tells us that you can plant them much earlier than more sensitive plants.

The earliest that you can plant hardy hibiscus 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 hardy hibiscus and expect a good harvest is probably September. Any later than that and your hardy hibiscus may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your hardy hibiscus indoors.

Last Frost Date

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

Since the USDA zone info for Oskaloosa is an average the actual date of last frost will vary from year to year. Half of the time in Oskaloosa it frosts late in the year after April 15 so make sure that you are ready to protect your hardy hibiscus if you have one of those late frosts.

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.