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.

In Washington you can determine 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 are one of those plants that can tolerate quite a bit of cold weather which means that you can get them planted much earlier than more sensitive plants.

The earliest that you can plant hardy hibiscus in Washington 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. Starting your hardy hibiscus indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Washington. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Washington is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Washington it frosts late in the year after April 15 be ready to protect your hardy hibiscus if you have a surprise late frost.

USDA Zone Info for Washington

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°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 -10°F.

Plants to Grow in Washington

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