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I often have 10 strains flowering at the same time, all of them will be covered in trichs so I figure there's more to it than being strain dependant.
Intense light for short periods of time, I use a light mover, is much more important than constant lower intensity light. I made my garden narrow, 3' x 8', and rotate my plants several times a day so each quarter of the plant is directly under the light at sometime through the day.
I've been using an LED as a spot for the last week or two of flower as well, It makes some difference and speeds trichnome ripening a bit.
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Fox Farm solubles
Overdrive - I use 1 1/2 tbs per gallon for the last 3 to 4 weeks.
Kool Bloom
Dark Energy
Super Nova
Hygrozyme
Liquid Karma
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Air pruning buckets to develop a good root system - this made a noticeable difference with my plants, both volume and trichs. I've been finding that buckets with holes drilled in the sides, lined with landscape fabric or window screen, a second bucket for the first to sit in until you want to kill the root tips a few days before watering.
https://www.rollitup.org/grow-room-design-setup/303229-diy-air-pruning-pot-experiment.html
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