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.

You can figure out when you can plant rhubarb in Portland by checking out the USDA zone info.

Planting Calendar for Rhubarb

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

Rhubarb do well in moderate cold which means that you can get them planted earlier than more sensitive plants.

The earliest that you can plant rhubarb in Portland is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant rhubarb and expect a good harvest is probably October. Any later than that and your rhubarb may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your rhubarb indoors.

Last Frost Date

In Portland the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 25°F.

Just be sure to remember that USDA zone info for Portland is just an average and the actual date of last frost changes from year to year. Half of the time in Portland last frost occurs after February 15 so be sure to be ready to cover your rhubarb in the event of a surprise late frost.

USDA Zone Info for Portland

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Portland

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