One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

A common way of making a decision about when it's the best time to plant hardy asters is to consult the USDA zone info for Yorkville.

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 mild cold which means that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant hardy asters in Yorkville 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 grow to maturity. Starting your hardy asters indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

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

USDA Zone Info for Yorkville

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 Yorkville

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