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.

It's possible to figure out when to plant aubrieta by reviewing the USDA zone info for Portland.

Planting Calendar for Aubrieta

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

Aubrieta do well in a little bit of cold which means that you can plant them just a bit earlier in the year than other frost tender plants.

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

Last Frost Date

The average date of last frost is April 15 in Portland. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Portland is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Portland you get surprised by a frost after April 15 be ready to cover your aubrieta if you have a surprise late frost.

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.