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.

A way of making a decision about when to plant hardy asters is to use the USDA zone info for Mill Creek.

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 just a tiny bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant hardy asters in Mill Creek 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 grow to maturity. You can get started a few weeks earlier by starting your hardy asters indoors.

Last Frost Date

In Mill Creek the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 15°F.

Keep in mind that USDA zone info for Mill Creek is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Mill Creek there is a last frost after March 15 be ready to cover your hardy asters in the event of a surprise late frost.

USDA Zone Info for Mill Creek

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Mill Creek

You may be interested in your other planting guides for Mill Creek.