One of the best tools that you have as gardeners to help us figure out 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.

The USDA zone info for Kennewick should be looked at to determine 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.

Ornamental Grasses are barely cold tolerant which tells us that you can start planting them slightly earlier than other frost tender plants.

The earliest that you can plant ornamental grasses in Kennewick 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 really do well. If you are starting your ornamental grasses indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Kennewick. You should expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Kennewick is just an average the actual date of last frost is different every year. Half of the time in Kennewick it frosts late in the year after April 15 so always be ready to cover your ornamental grasses if you have one of those late frosts.

USDA Zone Info for Kennewick

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Kennewick

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