One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Roy should be read to determine when you can plant hardy asters.

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.

You can plant hardy asters a bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant hardy asters in Roy 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. Any later than that and your hardy asters may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your hardy asters indoors.

Last Frost Date

The average date of last frost is April 15 in Roy. You can expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Roy is not always accurate the actual date of last frost will vary from year to year. Half of the time in Roy last frost occurs after April 15 so be sure to be ready to protect your hardy asters if you have one of those late frosts.

USDA Zone Info for Roy

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 Roy

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