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.

A common way of figuring out when it's possible to plant hardy asters is to check out the USDA zone info for Rocky River.

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 are barely cold tolerant which means that you can start planting them slightly earlier than more sensitive plants.

The earliest that you can plant hardy asters in Rocky River 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. Any later than that and your hardy asters may not have a chance to fully mature. You can get started a few weeks earlier by starting your hardy asters indoors.

Last Frost Date

On average the last frost is on April 15 in Rocky River. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Rocky River is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Rocky River you get a frost after April 15 so just be sure to be ready to cover your hardy asters in the event of a late frost.

USDA Zone Info for Rocky River

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 Rocky River

You may be interested in your other planting guides for Rocky River.