One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's a good idea to determine when to plant hemerocallis by checking out the USDA zone info for Washington.

Planting Calendar for Hemerocallis

Frost tolerance for hemerocallis:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Hemerocallis are moderately cold tolerant which means that you can get them planted earlier than more sensitive plants.

The earliest that you can plant hemerocallis 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 hemerocallis and expect a good harvest is probably September. If you wait any later than that and your hemerocallis may not have a chance to fully mature. If you are starting your hemerocallis indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Washington the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Washington is not always accurate the actual date of last frost changes from year to year. Since half of the time in Washington it frosts late in the year after April 15 be ready to cover your hemerocallis if you have one of those late frosts.

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.