One of the best tools that you have as gardeners to help us estimate 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.

The first opportunity to plant jerusalem artichokes in Grinnell can be figured out by referring to the USDA zone info.

Planting Calendar for Jerusalem artichokes

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

Jerusalem artichokes are one of those plants that can tolerate a little bit of cold weather which tells us that you can plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant jerusalem artichokes in Grinnell 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 jerusalem artichokes and expect a good harvest is probably September. Any later than that and your jerusalem artichokes may not have a chance to fully mature. If you are starting your jerusalem artichokes indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Grinnell. You can expect an average low temperature of -20°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Grinnell may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Grinnell you get a frost after April 15 be ready to protect your jerusalem artichokes in the event of a surprise late frost.

USDA Zone Info for Grinnell

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Grinnell

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