One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's a good idea to estimate when you can plant monarda by reviewing the USDA zone info for Iowa City.

Planting Calendar for Monarda

Frost tolerance for monarda:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since monarda are barely cold tolerant you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant monarda in Iowa City is March. However, you really should wait until April if you don't want to take any chances.

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

Last Frost Date

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

Since the USDA zone info for Iowa City may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Iowa City you get surprised by a frost after April 15 so always be ready to cover your monarda in the event of a late frost.

USDA Zone Info for Iowa City

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Iowa City

You may be interested in your other planting guides for Iowa City.