Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant hibiscus in Waterloo should be figured out by referring to the USDA zone info.

Planting Calendar for Hibiscus

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

It's probably a bad idea to plant hibiscus until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant hibiscus in Waterloo 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 hibiscus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your hibiscus may not have a chance to grow to maturity. Starting your hibiscus 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 Waterloo. You can expect an average low temperature of -20°F in the coldest months of winter.

Keep in mind that USDA zone info for Waterloo is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Waterloo there is a last frost after April 15 so always be ready to protect your hibiscus in the event of a surprise late frost.

USDA Zone Info for Waterloo

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 Waterloo

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