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.

It's possible to determine when it's the best time to plant hardy asters by referring to the USDA zone info for Broken Arrow.

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 plant them slightly earlier than other frost tender plants.

The earliest that you can plant hardy asters in Broken Arrow 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

In Broken Arrow the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 0°F.

Since the USDA zone info for Broken Arrow is just an average the actual date of last frost will vary from year to year. Since half of the time in Broken Arrow you get surprised by a frost after April 15 be ready to cover your hardy asters if you have a late frost.

USDA Zone Info for Broken Arrow

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Broken Arrow

You may be interested in your other planting guides for Broken Arrow.