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

In Portland you can determine when it's the best time to plant celosia by looking at the USDA zone info.

Planting Calendar for Celosia

Frost tolerance for celosia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

You can not plant celosia until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant celosia in Portland 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 celosia and expect a good harvest is probably September. 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 couple of weeks earlier by starting your celosia indoors.

Last Frost Date

The average date of last frost is February 15 in Portland. It might get as low as 25°F during the coldest months of winter.

Keep in mind that USDA zone info for Portland is an average and the actual date of last frost is different every year. Since half of the time in Portland you get surprised by a frost after February 15 be ready to protect your celosia in the event of a late frost.

USDA Zone Info for Portland

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Portland

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