One of the best tools that you have as gardeners to help us determine 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 USDA zone info for Duluth can be read to figure out when to plant regal geranium.

Planting Calendar for Regal Geranium

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

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

The earliest that you can plant regal geranium in Duluth 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 regal geranium and expect a good harvest is probably August. If you wait any later than that and your regal geranium may not have a chance to really do well. Starting your regal geranium indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in Duluth. In the coldest months of winter you should expect an average low temperature of -30°F.

Just be sure to remember that USDA zone info for Duluth is not always accurate and the actual date of last frost is different every year. Since half of the time in Duluth you get surprised by a frost after May 15 be ready to protect your regal geranium in the event of a surprise late frost.

USDA Zone Info for Duluth

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Duluth

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