Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Tualatin you will be able to figure out when you can plant ornamental grasses.

Planting Calendar for Ornamental Grasses

Frost tolerance for ornamental grasses:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since ornamental grasses are one of those plants that can tolerate a tiny bit of cold weather you can plant them just a tiny bit earlier in the year than more sensitive plants.

The earliest that you can plant ornamental grasses in Tualatin 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 ornamental grasses and expect a good harvest is probably August. You probably don't want to wait any later than that or else your ornamental grasses may not have a chance to fully mature. If you are starting your ornamental grasses indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Tualatin the average date of last frost happens on March 15. In the coldest months of winter you can expect an average low temperature of 15°F.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Tualatin and it is different every year. Half of the time in Tualatin there is a last frost after March 15 so always be ready to cover your ornamental grasses in the event of one of those late frosts.

USDA Zone Info for Tualatin

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 Tualatin

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