>>1723852>>1723851I have some planted in my garden and they've withstood -5 to -10°C on several occasions in the last 5 years (zone 8a)
Pic from last month, right now they're in bloom and also starting vegetative growth. I prune them heavily 2-3x a year and they've still become huge, though they had been tiny cuttings maybe a couple cm tall and wide when I planted them back in 2016