One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of getting a good idea when it's the best time to plant erysimum is to refer to the USDA zone info for Oskaloosa.

Planting Calendar for Erysimum

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

Erysimum are moderately cold tolerant which means that you can plant them a little bit earlier than other frost tender plants.

The earliest that you can plant erysimum 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 erysimum and expect a good harvest is probably September. You probably don't want to wait any later than that or else your erysimum may not have a chance to really do well. You can get started a few weeks earlier by starting your erysimum indoors.

Last Frost Date

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

Since the USDA zone info for Oskaloosa is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Oskaloosa you get surprised by a frost after April 15 so make sure that you are prepared to protect your erysimum if you have a surprise 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.