Before planting it is a good idea to find your USDA Zone info to estimate 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.

The USDA zone info for Grinnell should be reffered to in order to figure out when it's a good idea to plant carnation.

Planting Calendar for Carnation

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

Since carnation are very cold tolerant you can plant them earlier in the year than other plants that might not handle the cold.

The earliest that you can plant carnation 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 carnation and expect a good harvest is probably September. Any later than that and your carnation may not have a chance to really do well. If you are starting your carnation indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Grinnell. It might get as low as -20°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Grinnell and it changes from year to year. Since half of the time in Grinnell it frosts late in the year after April 15 be ready to protect your carnation in the event of a 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.