One of the first steps you take when you are estimating 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.

In Portland you can determine when it's the best time to plant angel's trumpets by checking out the USDA zone info.

Planting Calendar for Angel's Trumpets

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

Since angel's trumpets are one of those plants that can tolerate a tiny bit of cold weather you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant angel's trumpets 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 angel's trumpets and expect a good harvest is probably August. You probably don't want to wait any later than that or else your angel's trumpets may not have a chance to really do well. You can get started a couple of weeks earlier by starting your angel's trumpets indoors.

Last Frost Date

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

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Portland and it can change quite a bit from year to year. Since half of the time in Portland last frost occurs after March 15 be ready to cover your angel's trumpets if you have a surprise late frost.

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.