dna sequencing my man, its on !How the fuck can you determine sex of a plant or animal or human. You can't.
LOL
we know that good breeders have standardized their seed making rooms/conditions to optimize whats best for the plant/garden likely giving us an even mix of females and males in seed production. I've emailed back and forth with some about these things and learned how/what they do to accomplish this and try to replicate it in mine. stick with good breeders to get repeatable results. for example my flowering girls are solid milky white trichs in the week my breeders' say they will be.I've tried everything over the years. Picking seeds by shape, room temperature, day length, music(different types), humidity, talking to them calling everything a girl...
My best luck was 6 females out of 8. Worse luck, 2 females out 6. I've used a HID, box LED, and finally COBs with a mix of 3000k and 3500k.
With regular seeds it's a pull of a Law Vegas slot machine arm on what you get.