The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By checking out the USDA zone info for Washington you should be able to estimate when it's the best time to plant rhubarb.

Planting Calendar for Rhubarb

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

Since rhubarb are moderately cold tolerant you can plant them a little earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant rhubarb 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 rhubarb and expect a good harvest is probably September. If you wait any later than that and your rhubarb may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your rhubarb indoors.

Last Frost Date

In Washington the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

Remember that USDA zone info for Washington is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Washington you get surprised by a frost after April 15 be ready to cover your rhubarb in the event of a late frost.

USDA Zone Info for Washington

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Washington

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