One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Harwood Heights you can estimate when to plant hardy asters by checking out 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 are barely cold tolerant which tells us that you can start planting them slightly earlier than other frost tender plants.

The earliest that you can plant hardy asters in Harwood Heights 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 really do well. You can get started a couple of weeks earlier by starting your hardy asters indoors.

Last Frost Date

The average date of last frost is April 15 in Harwood Heights. You should expect an average low temperature of -15°F in the coldest months of winter.

Always keep in mind that USDA zone info for Harwood Heights is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Harwood Heights you get surprised by a frost after April 15 so always be ready to cover your hardy asters in the event of a surprise late frost.

USDA Zone Info for Harwood Heights

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 Harwood Heights

You may be interested in your other planting guides for Harwood Heights.