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.

It's a good idea to figure out when it's the best time to plant schizanthus by reviewing the USDA zone info for Grinnell.

Planting Calendar for Schizanthus

Frost tolerance for schizanthus:	Not tolerant of frost.
When to plant:	After the last frost has passed.

It's a bad idea to plant schizanthus until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant schizanthus in Grinnell is April. However, you really should wait until May if you don't want to take any chances.

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

Last Frost Date

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

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Grinnell and it is different every year. Half of the time in Grinnell there is a last frost after April 15 so just be sure to be ready to cover your schizanthus 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.