One of the best tools that you have as gardeners to help us estimate 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.

You will be able to figure out when it's a good idea to plant asters by looking at the USDA zone info for Vernal.

Planting Calendar for Asters

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

Asters are one of those plants that can tolerate a little bit of cold weather which means that you can start planting them earlier than other frost tender plants.

The earliest that you can plant asters in Vernal 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. You probably don't want to wait any later than that or else your asters may not have a chance to really do well. You can get started a few weeks earlier by starting your asters indoors.

Last Frost Date

The average date of last frost is April 15 in Vernal. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Vernal is an average the actual date of last frost changes from year to year. Half of the time in Vernal it frosts late in the year after April 15 so be sure to be ready to protect your asters if you have a late frost.

USDA Zone Info for Vernal

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 Vernal

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