One of the first steps you take when you are making a decision about 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.

You will be able to figure out when to plant pampas grass by using the USDA zone info for Umatilla.

Planting Calendar for Pampas Grass

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

Since pampas grass are not cold tolerant it's important to wait until after the last frost has passed before you can plant them.

The earliest that you can plant pampas grass in Umatilla 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 pampas grass and expect a good harvest is probably August. If you wait any later than that and your pampas grass may not have a chance to really do well. Starting your pampas grass indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Umatilla. In the coldest months of winter you should expect an average low temperature of 5°F.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Umatilla and it is different every year. Half of the time in Umatilla you get surprised by a frost after April 15 so make sure that you are ready to protect your pampas grass in the event of a late frost.

USDA Zone Info for Umatilla

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Umatilla

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