American Lagerstroemia speciosa or American Red Rocket Lagerstroemia speciosa, which is more resistant to low temperature, can it be planted in Qingdao, Shandong?

Very suitable for planting in Qingdao. Last year, some of the common Lagerstroemia indica introduced from Zhejiang suffered from frostbite, but the red-fireball Lagerstroemia indica, which was also introduced from Jiangxi Agriculture, Countryside and Farmers Company, was unscathed, because both American red-leaf Lagerstroemia indica and American red rocket Lagerstroemia indica were new varieties introduced from the United States. These three American red-fireball Lagerstroemia indica are collectively called American three red Lagerstroemia indica, which have different characteristics but the same cold resistance, and can resist the extreme low temperature of minus 18 degrees.