One of the first steps you take when you are determining your gardening schedule is find your 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.

The USDA zone info for Portland should be reffered to in order to determine when to plant spinach.

Planting Calendar for Spinach

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

Spinach are one of those plants that can tolerate a little bit of cold weather which tells us that you can plant them earlier than more sensitive plants.

The earliest that you can plant spinach 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 spinach and expect a good harvest is probably October. You probably don't want to wait any later than that or else your spinach may not have a chance to grow to maturity. If you are starting your spinach indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Portland the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Portland is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Portland you get a frost after February 15 so be sure to be ready to protect your spinach in the event of one of those late frosts.

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.