When to Plant Hardy Asters in Mount Horeb, WI

One of the first steps you take when you are determining 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.

It's possible to estimate when you can plant hardy asters by looking at the USDA zone info for Mount Horeb.


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 get them planted just a bit earlier than more sensitive plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant hardy asters
Possibly ok, but a risky time to plant hardy asters
Probably not a good time to plant hardy asters

The earliest that you can plant hardy asters in Mount Horeb 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 really do well. Starting your hardy asters indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Mount Horeb. You should expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Mount Horeb is not always accurate the actual date of last frost is different every year. Since half of the time in Mount Horeb you get a frost after April 15 be ready to cover your hardy asters if you have a surprise late frost.

USDA Zone Info for Mount Horeb

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Mount Horeb

You may be interested in your other planting guides for Mount Horeb.