GB,
Since I grow different strain with each grow I have nothing "dialed" in.
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I have been using Heads variation of the Lucas formula for coco, (6ml FloraMicro, 9ml FloraBloom with 3ml Cal/Mag instead of Epson and 3 to 5ml Silica).
Veg - Full rate
Week 1 thru 3 of 12/12 - Full rate - Flush
Week 4 - 4ml FM, 11ml FB plus C/M and silica - Flush
Week 5 - 2ml FM, 13ml FB plus C/M and silica - Flush
Week 6 - 0ml FM, 15ml FB plus C/M and silica - Flush
Week 7 - 15ml plus C/M and silica
Week 8 till harvest - Triple flush once with GH FloraClean, pH'ed water , then pH'ed water only.
Cut all water 4 to 5 day before chop.
This will be the first full grow doing it this way, so will report on outcome.
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Last grow, one Afghan regular, turned out to be a dude and the one before. I started using Heads formule two weeks after 12/12 and used full rates till one week prior to harvest the flushed.
I agree with you that you have to have some N in the mix till just prior to harvest.
Per Mr Nice Seeds - Indoors 10 weeks of flowering will be necessary to realize the immense resin production, they say 8 to 10 weeks.
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If I have the three fems I am hoping for I want to harvest one at 10 weeks, one at 11 and one at 12. This is all Trichome dependent as I want one with mostly clear trichs, one with mosly cloudy trichs and a some amber and one with cloudy and more amber so the weeks may be skewed.
Too much info?
Ok need to stop, it's time for the Super Bowl programming, so I think I will load a Super Bowl (mix of WW and Afghan), sit back and relax.
Peace out,
GR