One of the best tools that you have as gardeners to help us figure out 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 earliest that you can plant evolvulus in Grinnell should be figured out by looking at the USDA zone info.

Planting Calendar for Evolvulus

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

You really shouldn't plant evolvulus until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant evolvulus 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 evolvulus and expect a good harvest is probably August. If you wait any later than that and your evolvulus may not have a chance to grow to maturity. If you are starting your evolvulus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Remember that USDA zone info for Grinnell is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Grinnell you get a frost after April 15 be ready to protect your evolvulus if you have 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.