The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of making a decision about when you can plant asters is to refer to the USDA zone info for Louisville.

Planting Calendar for Asters

Frost tolerance for asters:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant asters a little bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant asters in Louisville is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant asters and expect a good harvest is probably September. If you wait any later than that and your asters may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your asters indoors.

Last Frost Date

On average the last frost has passed is on March 15 in Louisville. In the coldest months of winter you should expect an average low temperature of 10°F.

Since the USDA zone info for Louisville is just an average the actual date of last frost changes from year to year. Since half of the time in Louisville there is a last frost after March 15 be ready to protect your asters in the event of a surprise late frost.

USDA Zone Info for Louisville

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Louisville

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