COB led light from AliExpress

Probably good for a 12"x12" area, or slightly larger depending on its function.. supplementing 7-8 hours of sun? You may not need it on the perfectly sunny days, but maybe a good idea on cloudy days? 2000umol/s for ~8hours is as much as you want to provide in a 24 hour period. The cob can be used to prolong bloom but reducing dark period and holding off hormonal balance change. So, if you need an extra hour or two of light to prevent flowering or you think it was a cloudy day, it could be very useful, yes. On a day it gets at on of sun, you won't need it close to prevent flowering. you can cover a much larger area than 12x12 and perform that function.