Before planting it is a good idea to find your USDA Zone info to estimate your garden 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 Seattle should be reffered to in order to determine when it's the best time to plant hardy hibiscus.

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 can survive in a bit of cold which tells us that you can plant them much earlier in the year than other frost tender plants.

The earliest that you can plant hardy hibiscus in Seattle 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 grow to maturity. Starting your hardy hibiscus indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Seattle. It might get as low as 15°F during the coldest months of winter.

It's important to remember that USDA zone info for Seattle is just an average and the actual date of last frost changes from year to year. Half of the time in Seattle you get a frost after March 15 so always be ready to cover your hardy hibiscus if you have a late frost.

USDA Zone Info for Seattle

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 Seattle

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