Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant hardy asters in Walden should be determined by reviewing the USDA zone info.

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 means that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant hardy asters in Walden 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. If you are starting your hardy asters indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Walden. It might get as low as -15°F during the coldest months of winter.

Always keep in mind that USDA zone info for Walden is an average and the actual date of last frost changes from year to year. Half of the time in Walden you get surprised by a frost after April 15 so make sure that you are ready to cover your hardy asters if you have a surprise late frost.

USDA Zone Info for Walden

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 Walden

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