Vermiculite

My first grow I sprinkled in a few hand full's of Vermiculite into the soil..

A buddy recently told me that up to 1/3 Vermiculite stimulates growth?/ . when the roots hit the air pockets and chit?

Anyone have a good vermiculite to soil Ratio? as I want to transfer some seedlings..

my best advise would be to find what works for you. by mixing soil and soiless mixes yourself, you are trying to acheive an ideal growing medium for what ever your growing. cannabis happens to like a loose, airy, drainable soil. perlite and vermiculite added will help with drainage and aeroate the roots. alowing your soil to dry a lil between waterings. most people dont use more the 33% in there mix because and more and you have to water more frequently. i use prolly a 40% mix cause i use oceanforest AND am a cheap bastard as perlite is cheaper then the soil. i dont mind having to watermore often. i think the roots like it! like i said, what best works for you. every strain and enviroment is different and that has a major factor in determining your mix!

I grow 48 plants outside in only vermiculite and got 12 pounds. However i would say 1/3 v would be good.. through some perlite in to.

I've had a little too much vermiculite in my mix and it was making it hard for the pots to drain off between waterings and i ended up with medium PH problems so i spent last night washing all the vermiculite out with a siv so now im only using expanded clay with charcoal and a little perlite to fill in the gaps at the top , and already this morning my plants are looking much happeir with me.
Im gonna steer clear of it in future myself but i have found out since that u shouldn't use more then 1/3rd in the mix because it causes zinc issues when u use more then that, but i guess every strain is different because one of my strains were showing classic signs of zinc toxicity and the others were fine however i potted them all on the same day and they were all in the same medium.