One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of figuring out when to plant black eyed susans is to consult the USDA zone info for Portland.

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.

It's a bad idea to plant black eyed susans until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant black eyed susans in Portland is April. However, you really should wait until May 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 August. Any later than that and your black eyed susans may not have a chance to grow to maturity. You can get started a little bit earlier by starting your black eyed susans indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Portland. It might get as low as -15°F during the coldest months of winter.

It's important to remember that USDA zone info for Portland is not always accurate and the actual date of last frost is different every year. Half of the time in Portland you get surprised by a frost after April 15 so be sure to be ready to cover your black eyed susans if you have one of those late frosts.

USDA Zone Info for Portland

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°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 -10°F.

Plants to Grow in Portland

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