Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Portland it's a good idea to estimate when to plant xerianthemum.

Planting Calendar for Xerianthemum

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

Since xerianthemum do ok in moderate cold you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant xerianthemum in Portland is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant xerianthemum and expect a good harvest is probably August. You probably don't want to wait any later than that or else your xerianthemum may not have a chance to really do well. If you are starting your xerianthemum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Portland. In the coldest months of winter you should expect an average low temperature of 0°F.

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 protect your xerianthemum in the event of a late frost.

USDA Zone Info for Portland

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Portland

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