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.

A common way of making a decision about when you can plant hibiscus is to consult the USDA zone info for Willmar.

Planting Calendar for Hibiscus

Frost tolerance for hibiscus:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Hibiscus are not cold tolerant which tells us that you really should wait until it warms up after the last frost before you can plant them.

The earliest that you can plant hibiscus in Willmar 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 hibiscus and expect a good harvest is probably August. Any later than that and your hibiscus may not have a chance to really do well. If you are starting your hibiscus indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Willmar the average date of last frost happens on May 15. You can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Willmar may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Willmar it frosts late in the year after May 15 be ready to protect your hibiscus if you have one of those late frosts.

USDA Zone Info for Willmar

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Willmar

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