The USDA Zone info is a great tool for gardeners to help us estimate 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.

The USDA zone info for Portland should be read to figure out when to plant black eyed susans.

Planting Calendar for Black Eyed Susans

Frost tolerance for black eyed susans:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since black eyed susans require warm weather you need to wait until after the last frost before you can plant them.

The earliest that you can plant black eyed susans 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 black eyed susans and expect a good harvest is probably September. You probably don't want to wait any later than that or else your black eyed susans may not have a chance to fully mature. If you are starting your black eyed susans 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 February 15 in Portland. It might get as low as 25°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Portland is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Portland it frosts late in the year after February 15 be ready to protect your black eyed susans in the event of a surprise 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.