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 can estimate when it's the best time to plant pampas grass in Boulder by looking at 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.

Since pampas grass do not do well in cold weather it is important to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant pampas grass in Boulder 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. 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 couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Boulder. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Boulder is not always accurate the actual date of last frost changes from year to year. Since half of the time in Boulder you get surprised by a frost after April 15 be ready to protect your pampas grass in the event of a late frost.

USDA Zone Info for Boulder

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 Boulder

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