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.

By checking out the USDA zone info for Portland it's possible to figure out when it's the best time to plant roses.

Planting Calendar for Roses

Frost tolerance for roses:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Roses tend to make it in some cold which tells us that you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant roses 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 roses and expect a good harvest is probably September. Any later than that and your roses may not have a chance to grow to maturity. Starting your roses 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 April 15 in Portland. In the coldest months of winter you can expect an average low temperature of -15°F.

Keep in mind that USDA zone info for Portland may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Portland you get a frost after April 15 so always be ready to protect your roses in the event of a late frost.

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.