I have a 420 scope, but im fuckingcolor blind to this shit. Besides that my questin was how wll I know when these sativas will be about 3 weeks before harvest. I dont know what to look for to judge that soon.
Stop worring about trying to time your grow so you can flush or add other fancy sauce mixes,watch both the pistils & the trichomes,watching the pistils is as important as the trich's,they will tell you when its time to break out the microscope,dont even bother looking at the trich's until atleast 60% of the pistils have turned color,i dont even look at the trich's until im in the 80% range on the pistils then i take a peek,in my grows once the pistils reach around 80% red harvest will be within 1 week & at harvest the trichs will have a small amount of amber.
Worrying about flushing & additives will only fuk you up with your 1st grows,keep it simple,bag the idea of adding extras at the end of the grow & forget about extended flushing,both practices are highly debatable in their effect to final smoke quality,ive given up on flushing all together.
If you believe that flushing is a must for your grow by all means do it but wait until you have the desired trich color then do a quick flush.
