Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Decorah you can determine when it's a good idea to plant asparagus fern by checking out the USDA zone info.

Planting Calendar for Asparagus Fern

Frost tolerance for asparagus fern:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since asparagus fern do not do well in cold weather it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant asparagus fern in Decorah is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant asparagus fern and expect a good harvest is probably August. Any later than that and your asparagus fern may not have a chance to grow to maturity. Starting your asparagus fern indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Decorah the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -25°F.

Since the USDA zone info for Decorah is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Decorah last frost occurs after May 15 be ready to protect your asparagus fern in the event of a late frost.

USDA Zone Info for Decorah

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 Decorah

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