good question man... (and what ur doing is deffinitely working for you !!) i've considered it many times... i guess its basically because i am lazy. the way i do it now i only have to stay focused and "get'r done" for about 10 days every couple months. the rest of the time all i have to do is water the clones every other day... and water the moms every other day or every third day.
i think its also about economy of motion... or... economy of scale. i poke holes in all the clone cups at one time. i prepare all the medium at once. i take all the clones at once. i only have to mix up the clone solution once. I harvest all the plants at once. I think i'd go insane if i had to do all that stuff every few days. It'd be like a never-ending to-do list. and i already have a full-time 9 to 5 job.
but ever since i was like 18 (the last 16 years)... i've had this recurring dream of walking down a dark path in a secret marijunana garden... a garden in which the plants are all neatly arranged by height... and go from shortest to tallest (different ages). sorry, just felt like sharing
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I currently have 5 plants under 2 600s. Vegging under another 600. Started flowering on April 10, they were cloned in late January. So 8/9 weeks vegging. I'll yield 20 oz. Lined up right behind those are 15 more which were cloned April 1, from the current flowering batch. They will have 90 days veg because I wanted to finish my current flower (I hate mixing and staggering grows, I always fuck up the nutrients) and I'll be away the last week of June. Then I come back and chop and put in the15 for my 'October Surprise'. I still have 15 MORE clones, that I haven't put in big containers yet, so I guess I'm cloned up for the rest of the year!