The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of making a decision about when you can plant common hollyhock is to refer to the USDA zone info for Washington.

Planting Calendar for Common hollyhock

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

Common hollyhock do well in moderate cold which tells us that you can plant them a little bit earlier than other frost tender plants.

The earliest that you can plant common hollyhock 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 common hollyhock and expect a good harvest is probably September. If you wait any later than that and your common hollyhock may not have a chance to fully mature. You can get started a little bit earlier by starting your common hollyhock indoors.

Last Frost Date

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

Since the USDA zone info for Washington may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Washington there is a last frost after April 15 so make sure that you are prepared to protect your common hollyhock 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.