One of the best tools that you have as gardeners to help us determine 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 determining when you can plant asters is to look at the USDA zone info for Tomah.

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 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 Tomah 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 asters and expect a good harvest is probably August. If you wait any later than that and your asters may not have a chance to really do well. Starting your asters indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Tomah the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Tomah may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Tomah it frosts late in the year after May 15 so just be sure to be ready to cover your asters if you have a surprise late frost.

USDA Zone Info for Tomah

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Tomah

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