Germed 9 seeds in 2 runs 9/9 germed and 9/9 males. I think I have 2seeds left.
I've read many places and I try to follow it because it works for me but there are techniques to encourage high female ratios. Seeds are not predetermined sex and environmental factors can affect sex.
Supposedly you want
14/10 hours of light for the first 2-3 weeks the seedlings are above ground
high ratio of blue spectrum
cooler temperatures
higher nitrogen, lower PK
wetter soil rather than dry soil
There might be a few others but try those and see if that helps you. I'm not sure if the science is accurate but like I said it definitely works for me. Since I started using the technique 7 or 8 years ago I don't think I've had worse than 50/50 ratios and usually hit better than 50%. The last few beans I popped, 4/5 goji og, 5/8 Miyagi (one of my crosses), 4/8 Miyagi again. I currently have 5 grapes 13 that I didn't do the 14/10 for 2 weeks because I had clones going so I'll see what that does for the ratio but fingers crossed. Cheers