One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of determining when to plant mustard greens is to look at the USDA zone info for Portland.

Planting Calendar for Mustard greens

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

You can plant mustard greens a little bit earlier in the year because they do well in moderate cold.

The earliest that you can plant mustard greens in Portland 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 mustard greens and expect a good harvest is probably September. You probably don't want to wait any later than that or else your mustard greens may not have a chance to grow to maturity. Starting your mustard greens indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Portland is not always accurate the actual date of last frost will vary from year to year. Half of the time in Portland you get a frost after April 15 so make sure that you are prepared to cover your mustard greens in the event of one of those late frosts.

USDA Zone Info for Portland

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 Portland

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