Dimming 220v LED lights

http://www.ebay.com.au/itm/Genuine-DRIVERLESS-Full-Spectrum-COB-LED-Chip-50W-Plant-Grow-Light-220v-DIY/

what do you think could work best for a dozen of these hooked up ?

As far as I know, those are NOT dimmable...

Thread split. @MasterCATZ, do not hijack.