I was quoting from a nursery site. However, this plant seems to be introduced by Garden Debut. Link below. There's not really much information on there. I do not know where to look up plant patent information. Usually though if a plant is bred specifically for hardiness, I would expect some information about that. Indian Hawthorns are not reliably hardy in zone 7A, and to see one listed as zone 6 is amazing. SO.....I would rather hear from someone who has actually grown the plant in their zone 7 garden (especially after THIS winter!) than trust a grower or plant introducer who may have been rushed in getting the plant to market before rigorously trialing it. For example, look at the many gardenias hitting the market that are listed as zone 6. I don't know of ANY gardenias that will not be damaged in zone 6 without major protection. But they put that on the tag. Here is a link that might be useful: Garden Debut - Redbird ('sPg-3-003')

The pink ones in particular often suffer from an incurable fungus.

Hope for a miracle. Make plans for something hardier for replacments

We had no leaf spot or sunburn problems with 'Ballerina' in a northwest facing bed that gets full sun from about 10:00 am to 3:00 pm during the summer. Usually looked very nice, but were in a spot we started to limit to one deep supplemental watering a month. While they did survived on this through the dry heatwave of 2011, they suffered worse than most everything else in the bed, so were eventually replaced with autumn sage and flame acanthus. Would not have any reservations about using them around Dallas where they get at least a bit of late afternoon shade in the summer and weekly irrigation as needed. May also work well in other exposures, but this is all we are familiar with.