The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when it's a good idea to plant celosia in Portland by reviewing the USDA zone info.

Planting Calendar for Celosia

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

It's probably not a good idea to plant celosia until after the last frost because they are not cold tolerant.

The earliest that you can plant celosia in Portland 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 celosia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your celosia may not have a chance to fully mature. You can get started a few weeks earlier by starting your celosia indoors.

Last Frost Date

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

Remember that USDA zone info for Portland is an average and the actual date of last frost will vary from year to year. Since half of the time in Portland there is a last frost after April 15 be ready to cover your celosia in the event of a surprise late frost.

USDA Zone Info for Portland

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 Portland

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