The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By referring to the USDA zone info for Portland it's possible to estimate when it's a good idea to plant artemesia.

Planting Calendar for Artemesia

Frost tolerance for artemesia:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Artemesia do ok in mild cold which tells us that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant artemesia 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 artemesia and expect a good harvest is probably September. If you wait any later than that and your artemesia may not have a chance to really do well. Starting your artemesia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Portland. It might get as low as 25°F during the coldest months of winter.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Portland and it is different every year. Since half of the time in Portland it frosts late in the year after February 15 be ready to protect your artemesia in the event of a 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.