The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. 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 Delafield can be reviewed to figure out when it's a good idea to plant tropical hibiscus.

Planting Calendar for Tropical Hibiscus

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

You should not plant tropical hibiscus until after the last frost because they are not cold tolerant.

The earliest that you can plant tropical hibiscus in Delafield 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 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. If you are starting your tropical hibiscus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Delafield. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Delafield may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Delafield it frosts late in the year after April 15 so make sure that you are prepared to protect your tropical hibiscus if you have a surprise late frost.

USDA Zone Info for Delafield

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 Delafield

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