Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By looking at the USDA zone info for Hillsboro you will be able to estimate when you can plant celosia.

Planting Calendar for Celosia

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

It's probably not a good idea to plant celosia until after all chance of frost has passed because they require warm weather.

The earliest that you can plant celosia in Hillsboro 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. Any later than that and your celosia may not have a chance to really do well. Starting your celosia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Hillsboro the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Hillsboro is an average the actual date of last frost changes from year to year. Half of the time in Hillsboro you get a frost after April 15 so make sure that you are prepared to cover your celosia in the event of a late frost.

USDA Zone Info for Hillsboro

Here is the info for USDA Zone 6a.

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

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

Plants to Grow in Hillsboro

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