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

In Hillsboro you can estimate when you can plant hardy hibiscus by looking at the USDA zone info.

Planting Calendar for Hardy Hibiscus

Frost tolerance for hardy hibiscus:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Hardy Hibiscus do well in cold which means that you can get them planted much earlier than other frost tender plants.

The earliest that you can plant hardy hibiscus in Hillsboro is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant hardy hibiscus and expect a good harvest is probably September. Any later than that and your hardy hibiscus may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your hardy hibiscus indoors.

Last Frost Date

On average the last frost is on March 15 in Hillsboro. In the coldest months of winter you should expect an average low temperature of 15°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Hillsboro and it changes from year to year. Half of the time in Hillsboro you get a frost after March 15 so just be sure to be ready to protect your hardy hibiscus in the event of a surprise late frost.

USDA Zone Info for Hillsboro

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Hillsboro

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