Before planting it is a good idea to find your USDA Zone info to determine 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.

In Oregon you can figure out when you can plant hardy asters by using the USDA zone info.

Planting Calendar for Hardy Asters

Frost tolerance for hardy asters:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Hardy Asters tend to make it in very little cold which tells us that you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant hardy asters in Oregon 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 hardy asters and expect a good harvest is probably August. You probably don't want to wait any later than that or else your hardy asters may not have a chance to really do well. Starting your hardy asters indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Oregon. It might get as low as -5°F during the coldest months of winter.

It's important to remember that USDA zone info for Oregon is not always accurate and the actual date of last frost is different every year. Half of the time in Oregon you get surprised by a frost after April 15 so be sure to be ready to cover your hardy asters if you have a surprise late frost.

USDA Zone Info for Oregon

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°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 0°F.

Plants to Grow in Oregon

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