One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant pampas grass in Portland can be determined by checking out the USDA zone info.

Planting Calendar for Pampas Grass

Frost tolerance for pampas grass:	Not tolerant of frost.
When to plant:	After the last frost.

You really shouldn't plant pampas grass until after the last frost because they require warm weather.

The earliest that you can plant pampas grass 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 pampas grass and expect a good harvest is probably September. You probably don't want to wait any later than that or else your pampas grass may not have a chance to fully mature. You can get started a little bit earlier by starting your pampas grass indoors.

Last Frost Date

The average date of last frost is February 15 in Portland. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Portland may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Portland you get surprised by a frost after February 15 be ready to cover your pampas grass if you have 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.