One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By reviewing the USDA zone info for Madison you should be able to estimate when it's a good idea to plant hardy asters.

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.

You can plant hardy asters a bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant hardy asters in Madison 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 few weeks earlier by starting your hardy asters indoors.

Last Frost Date

The average date of last frost is April 15 in Madison. In the coldest months of winter you should expect an average low temperature of -10°F.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Madison and it will vary from year to year. Since half of the time in Madison there is a last frost after April 15 be ready to cover your hardy asters in the event of one of those late frosts.

USDA Zone Info for Madison

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 Madison

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