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

It's possible to estimate when it's the best time to plant aubrieta by using 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 are one of those plants that can tolerate a little bit of cold weather which tells us that you can start planting them earlier than plants that are more sensitive to the cold.

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. Any later than that and your aubrieta may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your aubrieta indoors.

Last Frost Date

The average date of last frost is March 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 may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Portland you get surprised by a frost after March 15 so be sure to be ready to cover your aubrieta if you have one of those late frosts.

USDA Zone Info for Portland

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Portland

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