One of the best tools that you have as gardeners to help us estimate 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.

The first opportunity to plant tropical hibiscus in Duluth can be determined by looking at the USDA zone info.

Planting Calendar for Tropical Hibiscus

Frost tolerance for tropical hibiscus:	Not tolerant of frost.
When to plant:	After the last frost.

Tropical Hibiscus require warm weather which means that it is important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant tropical hibiscus in Duluth is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant tropical hibiscus and expect a good harvest is probably August. If you wait any later than that and your tropical hibiscus may not have a chance to fully mature. You can get started a few weeks earlier by starting your tropical hibiscus indoors.

Last Frost Date

The average date of last frost is May 15 in Duluth. In the coldest months of winter you can expect an average low temperature of -30°F.

Remember that USDA zone info for Duluth is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Duluth you get a frost after May 15 be ready to protect your tropical hibiscus if you have a 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.